Search Results

Search found 163 results on 7 pages for 'pthread'.

Page 6/7 | < Previous Page | 2 3 4 5 6 7  | Next Page >

• Passing Data to Multi Threads

  - by alaamh

  I study this code from some book: #include <pthread.h> #include <stdio.h> /* Parameters to print_function. */ struct char_print_parms { /* The character to print. */ char character; /* The number of times to print it. */ int count; }; /* Prints a number of characters to stderr, as given by PARAMETERS, which is a pointer to a struct char_print_parms. */ void* char_print(void* parameters) { /* Cast the cookie pointer to the right type. */ struct char_print_parms* p = (struct char_print_parms*) parameters; int i; for (i = 0; i < p->count; ++i) fputc(p->character, stderr); return NULL; } /* The main program. */ int main() { pthread_t thread1_id; pthread_t thread2_id; struct char_print_parms thread1_args; struct char_print_parms thread2_args; /* Create a new thread to print 30,000 ’x’s. */ thread1_args.character = 'x'; thread1_args.count = 30000; pthread_create(&thread1_id, NULL, &char_print, &thread1_args); /* Create a new thread to print 20,000 o’s. */ thread2_args.character = 'o'; thread2_args.count = 20000; pthread_create(&thread2_id, NULL, &char_print, &thread2_args); usleep(20); return 0; } after running this code, I see different result each time. and some time corrupted result. what is wrong and what the correct way to do that?

  Read the article

• How to multi-thread this?

  - by WilliamKF

  I wish to have two threads. The first thread1 occasionally calls the following pseudo function: void waitForThread2() { if (thread2 is not idle) { return; } notifyThread2IamReady(); while (thread2IsExclusive) { } } The second thread2 is forever in the following pseudo loop: for (;;) { Notify thread1 I am idle. while (!thread1IsReady()) { } Notify thread1 I am exclusive. Do some work while thread1 is blocked. Notify thread1 I am busy. Do some work in parallel with thread1. } What is the best way to write this such that both thread1 and thread2 are kept as busy as possible on a machine with multiple cores. I would like to avoid long delays between notification in one thread and detection by the other. I tried using pthread condition variables but found the delay between thread2 doing 'notify thread1 I am busy' and the loop in waitForThread2() on thear2IsExclusive() can be up to almost one second delay. I then tried using a volatile sig_atomic_t shared variable to control the same, but something is going wrong, so I must not be doing it correctly.

  Read the article

• How should a multi-threaded C application handle a failed malloc()?

  - by user294463

  A part of an application I'm working on is a simple pthread-based server that communicates over a TCP/IP socket. I am writing it in C because it's going to be running in a memory constrained environment. My question is: what should the program do if one of the threads encounters a malloc() that returns NULL? Possibilities I've come up with so far: No special handling. Let malloc() return NULL and let it be dereferenced so that the whole thing segfaults. Exit immediately on a failed malloc(), by calling abort() or exit(-1). Assume that the environment will clean everything up. Jump out of the main event loop and attempt to pthread_join() all the threads, then shut down. The first option is obviously the easiest, but seems very wrong. The second one also seems wrong since I don't know exactly what will happen. The third option seems tempting except for two issues: first, all of the threads need not be joined back to the main thread under normal circumstances and second, in order to complete the thread execution, most of the remaining threads will have to call malloc() again anyway. What shall I do?

  Read the article

• compile error:c language in telnet(linux)

  - by lilyrose07

  #include<stdio.h> #include<unistd.h> #include<stdlib.h> #include<pthread.h> int count=0; void *thread_function(void *arg) { while(count<10) { if(count%2==1) { count++; } else {sleep(1);} } } int main(int argc,int *argv) { int res; pthread_t a_thread[2]; void *thread_result; int n; while(count<10) { if(count%2==0) {printf("%d",count); count++; } else{sleep(1);} } for(n=0;n<2;n++) { pthread_create(&(a_thread[n]),NULL,thread_function,NULL); } while(count==9) {pthread_join(a_thread[0],&thread_result); } while(count==10) { pthread_join(a_thread[1],&thread_result); } printf("%d",count); return 0; } in telnet,linux i write gcc za.c error list: undefined reference to pthread_create,pthread_join in function 'main' //why??

  Read the article

• Getting error while install mod_wsgi on centos6.3 with python 2.7

  - by user825904

  In initially installed yum install mod_wsgi and i think it was linked with python 2.6 Now is there any way to link it with 2.7 I tried configuring from the source and i get this error apxs -c -I/usr/local/include/python2.7 -DNDEBUG mod_wsgi.c -L/usr/local/lib -L/usr/local/lib/python2.7/config -lpython2.7 -lpthread -ldl -lutil -lm /usr/lib64/apr-1/build/libtool --silent --mode=compile gcc -prefer-pic -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-buffer-size=4 -m64 -mtune=generic -Wformat-security -fno-strict-aliasing -DLINUX=2 -D_REENTRANT -D_GNU_SOURCE -pthread -I/usr/include/httpd -I/usr/include/apr-1 -I/usr/include/apr-1 -I/usr/local/include/python2.7 -DNDEBUG -c -o mod_wsgi.lo mod_wsgi.c && touch mod_wsgi.slo In file included from /usr/local/include/python2.7/Python.h:8, from mod_wsgi.c:142: /usr/local/include/python2.7/pyconfig.h:1161:1: warning: "_POSIX_C_SOURCE" redefined In file included from /usr/include/sys/types.h:26, from /usr/include/apr-1/apr-x86_64.h:127, from /usr/include/apr-1/apr.h:19, from /usr/include/httpd/ap_config.h:25, from /usr/include/httpd/httpd.h:43, from mod_wsgi.c:34: /usr/include/features.h:162:1: warning: this is the location of the previous definition In file included from /usr/local/include/python2.7/Python.h:8, from mod_wsgi.c:142: /usr/local/include/python2.7/pyconfig.h:1183:1: warning: "_XOPEN_SOURCE" redefined In file included from /usr/include/sys/types.h:26, from /usr/include/apr-1/apr-x86_64.h:127, from /usr/include/apr-1/apr.h:19, from /usr/include/httpd/ap_config.h:25, from /usr/include/httpd/httpd.h:43, from mod_wsgi.c:34: /usr/include/features.h:164:1: warning: this is the location of the previous definition mod_wsgi.c: In function ‘wsgi_server_group’: mod_wsgi.c:991: warning: unused variable ‘value’ mod_wsgi.c: In function ‘Log_isatty’: mod_wsgi.c:1665: warning: unused variable ‘result’ mod_wsgi.c: In function ‘Log_writelines’: mod_wsgi.c:1802: warning: unused variable ‘msg’ mod_wsgi.c: In function ‘Adapter_output’: mod_wsgi.c:3087: warning: unused variable ‘n’ mod_wsgi.c: In function ‘Adapter_file_wrapper’: mod_wsgi.c:4138: warning: unused variable ‘result’ mod_wsgi.c: In function ‘wsgi_python_term’: mod_wsgi.c:5850: warning: unused variable ‘tstate’ mod_wsgi.c:5849: warning: unused variable ‘interp’ mod_wsgi.c: In function ‘wsgi_python_child_init’: mod_wsgi.c:7050: warning: unused variable ‘l’ mod_wsgi.c:6948: warning: unused variable ‘interp’ mod_wsgi.c: In function ‘wsgi_add_import_script’: mod_wsgi.c:7701: warning: unused variable ‘error’ mod_wsgi.c: In function ‘wsgi_add_handler_script’: mod_wsgi.c:8179: warning: unused variable ‘dconfig’ mod_wsgi.c:8178: warning: unused variable ‘sconfig’ mod_wsgi.c: In function ‘wsgi_hook_handler’: mod_wsgi.c:9375: warning: suggest parentheses around assignment used as truth value mod_wsgi.c:9377: warning: suggest parentheses around assignment used as truth value mod_wsgi.c:9379: warning: suggest parentheses around assignment used as truth value mod_wsgi.c:9383: warning: suggest parentheses around assignment used as truth value mod_wsgi.c:9403: warning: suggest parentheses around assignment used as truth value mod_wsgi.c:9405: warning: suggest parentheses around assignment used as truth value mod_wsgi.c:9408: warning: suggest parentheses around assignment used as truth value mod_wsgi.c: In function ‘wsgi_daemon_worker’: mod_wsgi.c:10819: warning: unused variable ‘duration’ mod_wsgi.c:10818: warning: unused variable ‘start’ mod_wsgi.c: In function ‘wsgi_hook_daemon_handler’: mod_wsgi.c:13172: warning: unused variable ‘i’ mod_wsgi.c:13170: warning: unused variable ‘elts’ mod_wsgi.c:13169: warning: unused variable ‘head’ mod_wsgi.c: At top level: mod_wsgi.c:8142: warning: ‘wsgi_set_user_authoritative’ defined but not used mod_wsgi.c:15251: warning: ‘wsgi_hook_check_user_id’ defined but not used /usr/lib64/apr-1/build/libtool --silent --mode=link gcc -o mod_wsgi.la -rpath /usr/lib64/httpd/modules -module -avoid-version mod_wsgi.lo -L/usr/local/lib -L/usr/local/lib/python2.7/config -lpython2.7 -lpthread -ldl -lutil -lm /usr/bin/ld: /usr/local/lib/libpython2.7.a(abstract.o): relocation R_X86_64_32 against `.rodata.str1.8' can not be used when making a shared object; recompile with -fPIC /usr/local/lib/libpython2.7.a: could not read symbols: Bad value collect2: ld returned 1 exit status apxs:Error: Command failed with rc=65536 . make: *** [mod_wsgi.la] Error 1 Waiting for Graham

  Read the article

• Getting error while installing mod_wsgi in centos

  - by user825904

  I have reinstalled python with enable shared [root@master mod_wsgi-3.4]# make clean rm -rf .libs rm -f mod_wsgi.o mod_wsgi.la mod_wsgi.lo mod_wsgi.slo mod_wsgi.loT rm -f config.log config.status rm -rf autom4te.cache [root@master mod_wsgi-3.4]# LD_RUN_PATH=/usr/local/lib make apxs -c -I/usr/local/include/python2.7 -DNDEBUG mod_wsgi.c -L/usr/local/lib -L/usr/local/lib/python2.7/config -lpython2.7 -lpthread -ldl -lutil -lm /usr/lib64/apr-1/build/libtool --silent --mode=compile gcc -prefer-pic -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-buffer-size=4 -m64 -mtune=generic -Wformat-security -fno-strict-aliasing -DLINUX=2 -D_REENTRANT -D_GNU_SOURCE -pthread -I/usr/include/httpd -I/usr/include/apr-1 -I/usr/include/apr-1 -I/usr/local/include/python2.7 -DNDEBUG -c -o mod_wsgi.lo mod_wsgi.c && touch mod_wsgi.slo In file included from /usr/local/include/python2.7/Python.h:8, from mod_wsgi.c:142: /usr/local/include/python2.7/pyconfig.h:1161:1: warning: "_POSIX_C_SOURCE" redefined In file included from /usr/include/sys/types.h:26, from /usr/include/apr-1/apr-x86_64.h:127, from /usr/include/apr-1/apr.h:19, from /usr/include/httpd/ap_config.h:25, from /usr/include/httpd/httpd.h:43, from mod_wsgi.c:34: /usr/include/features.h:162:1: warning: this is the location of the previous definition In file included from /usr/local/include/python2.7/Python.h:8, from mod_wsgi.c:142: /usr/local/include/python2.7/pyconfig.h:1183:1: warning: "_XOPEN_SOURCE" redefined In file included from /usr/include/sys/types.h:26, from /usr/include/apr-1/apr-x86_64.h:127, from /usr/include/apr-1/apr.h:19, from /usr/include/httpd/ap_config.h:25, from /usr/include/httpd/httpd.h:43, from mod_wsgi.c:34: /usr/include/features.h:164:1: warning: this is the location of the previous definition mod_wsgi.c: In function ‘wsgi_server_group’: mod_wsgi.c:991: warning: unused variable ‘value’ mod_wsgi.c: In function ‘Log_isatty’: mod_wsgi.c:1665: warning: unused variable ‘result’ mod_wsgi.c: In function ‘Log_writelines’: mod_wsgi.c:1802: warning: unused variable ‘msg’ mod_wsgi.c: In function ‘Adapter_output’: mod_wsgi.c:3087: warning: unused variable ‘n’ mod_wsgi.c: In function ‘Adapter_file_wrapper’: mod_wsgi.c:4138: warning: unused variable ‘result’ mod_wsgi.c: In function ‘wsgi_python_term’: mod_wsgi.c:5850: warning: unused variable ‘tstate’ mod_wsgi.c:5849: warning: unused variable ‘interp’ mod_wsgi.c: In function ‘wsgi_python_child_init’: mod_wsgi.c:7050: warning: unused variable ‘l’ mod_wsgi.c:6948: warning: unused variable ‘interp’ mod_wsgi.c: In function ‘wsgi_add_import_script’: mod_wsgi.c:7701: warning: unused variable ‘error’ mod_wsgi.c: In function ‘wsgi_add_handler_script’: mod_wsgi.c:8179: warning: unused variable ‘dconfig’ mod_wsgi.c:8178: warning: unused variable ‘sconfig’ mod_wsgi.c: In function ‘wsgi_hook_handler’: mod_wsgi.c:9375: warning: suggest parentheses around assignment used as truth value mod_wsgi.c:9377: warning: suggest parentheses around assignment used as truth value mod_wsgi.c:9379: warning: suggest parentheses around assignment used as truth value mod_wsgi.c:9383: warning: suggest parentheses around assignment used as truth value mod_wsgi.c:9403: warning: suggest parentheses around assignment used as truth value mod_wsgi.c:9405: warning: suggest parentheses around assignment used as truth value mod_wsgi.c:9408: warning: suggest parentheses around assignment used as truth value mod_wsgi.c: In function ‘wsgi_daemon_worker’: mod_wsgi.c:10819: warning: unused variable ‘duration’ mod_wsgi.c:10818: warning: unused variable ‘start’ mod_wsgi.c: In function ‘wsgi_hook_daemon_handler’: mod_wsgi.c:13172: warning: unused variable ‘i’ mod_wsgi.c:13170: warning: unused variable ‘elts’ mod_wsgi.c:13169: warning: unused variable ‘head’ mod_wsgi.c: At top level: mod_wsgi.c:8142: warning: ‘wsgi_set_user_authoritative’ defined but not used mod_wsgi.c:15251: warning: ‘wsgi_hook_check_user_id’ defined but not used /usr/lib64/apr-1/build/libtool --silent --mode=link gcc -o mod_wsgi.la -rpath /usr/lib64/httpd/modules -module -avoid-version mod_wsgi.lo -L/usr/local/lib -L/usr/local/lib/python2.7/config -lpython2.7 -lpthread -ldl -lutil -lm

  Read the article

• APC PHP cache size does not exceed 32MB, even though settings allow for more

  - by hardy101

  I am setting up APC (v 3.1.9) on a high-traffic WordPress installation on CentOS 6.0 64 bit. I have figured out many of the quirks with APC, but something is still not quite right. No matter what settings I change, APC never actually caches more than 32MB. I'm trying to bump it up to 256 MB. 32MB is a default amount for apc.shm_size, so I am wondering if it's stuck there somehow. I have run the following echo '2147483648' > /proc/sys/kernel/shmmax to increase my system's shared memory to 2G (half of my 4G box). Then ran ipcs -lm which returns ------ Shared Memory Limits -------- max number of segments = 4096 max seg size (kbytes) = 2097152 max total shared memory (kbytes) = 8388608 min seg size (bytes) = 1 Also made a change in /etc/sysctl.conf then ran sysctl -p to make the settings stick on the server. Rebooted, too, for good measure. In my APC settings, I have mmap enabled (which happens by default in recent versions of APC). php.ini looks like: apc.stat=0 apc.shm_size="256M" apc.max_file_size="10M" apc.mmap_file_mask="/tmp/apc.XXXXXX" apc.ttl="7200" I am aware that mmap mode will ignore references to apc.shm_segments, so I have left it out with default 1. phpinfo() indicates the following about APC: Version 3.1.9 APC Debugging Disabled MMAP Support Enabled MMAP File Mask /tmp/apc.bPS7rB Locking type pthread mutex Locks Serialization Support php Revision $Revision: 308812 $ Build Date Oct 11 2011 22:55:02 Directive Local Value apc.cache_by_default On apc.canonicalize O apc.coredump_unmap Off apc.enable_cli Off apc.enabled On On apc.file_md5 Off apc.file_update_protection 2 apc.filters no value apc.gc_ttl 3600 apc.include_once_override Off apc.lazy_classes Off apc.lazy_functions Off apc.max_file_size 10M apc.mmap_file_mask /tmp/apc.bPS7rB apc.num_files_hint 1000 apc.preload_path no value apc.report_autofilter Off apc.rfc1867 Off apc.rfc1867_freq 0 apc.rfc1867_name APC_UPLOAD_PROGRESS apc.rfc1867_prefix upload_ apc.rfc1867_ttl 3600 apc.serializer default apc.shm_segments 1 apc.shm_size 256M apc.slam_defense On apc.stat Off apc.stat_ctime Off apc.ttl 7200 apc.use_request_time On apc.user_entries_hint 4096 apc.user_ttl 0 apc.write_lock On apc.php reveals the following graph, no matter how long the server runs (cache size fluctuates and hovers at just under 32MB. See image http://i.stack.imgur.com/2bwMa.png You can see that the cache is trying to allocate 256MB, but the brown piece of the pie keeps getting recycled at 32MB. This is confirmed as refreshing the apc.php page shows cached file counts that move up and down (implying that the cache is not holding onto all of its files). Does anyone have an idea of how to get APC to use more than 32 MB for its cache size?? **Note that the identical behavior occurs for eaccelerator, xcache, and APC. I read here: http://www.litespeedtech.com/support/forum/archive/index.php/t-5072.html that suEXEC could cause this problem.

  Read the article

• Vim digraphs is not working

  - by Hauleth

  I've tried to input digraphs in Vim (without vi compatibility), and unfortunately I can't. After using ControlKP * it should input big greek pi letter. I've also tried using PBS * with :set digraph, but no success either. My gvim --version output: VIM - Vi IMproved 7.3 (2010 Aug 15, compiled Oct 23 2012 18:42:18) Included patches: 1-712 Compiled by ArchLinux Big version with GTK2 GUI. Features included (+) or not (-): +arabic +autocmd +balloon_eval +browse ++builtin_terms +byte_offset +cindent +clientserver +clipboard +cmdline_compl +cmdline_hist +cmdline_info +comments +conceal +cryptv +cscope +cursorbind +cursorshape +dialog_con_gui +diff +digraphs +dnd -ebcdic +emacs_tags +eval +ex_extra +extra_search +farsi +file_in_path +find_in_path +float +folding -footer +fork() +gettext -hangul_input +iconv +insert_expand +jumplist +keymap +langmap +libcall +linebreak +lispindent +listcmds +localmap +lua +menu +mksession +modify_fname +mouse +mouseshape +mouse_dec +mouse_gpm -mouse_jsbterm +mouse_netterm +mouse_sgr -mouse_sysmouse +mouse_urxvt +mouse_xterm +multi_byte +multi_lang -mzscheme +netbeans_intg +path_extra +perl +persistent_undo +postscript +printer -profile +python -python3 +quickfix +reltime +rightleft +ruby +scrollbind +signs +smartindent -sniff +startuptime +statusline -sun_workshop +syntax +tag_binary +tag_old_static -tag_any_white -tcl +terminfo +termresponse +textobjects +title +toolbar +user_commands +vertsplit +virtualedit +visual +visualextra +viminfo +vreplace +wildignore +wildmenu +windows +writebackup +X11 -xfontset +xim +xsmp_interact +xterm_clipboard -xterm_save system vimrc file: "/etc/vimrc" user vimrc file: "$HOME/.vimrc" user exrc file: "$HOME/.exrc" system gvimrc file: "/etc/gvimrc" user gvimrc file: "$HOME/.gvimrc" system menu file: "$VIMRUNTIME/menu.vim" fall-back for $VIM: "/usr/share/vim" Compilation: gcc -c -I. -Iproto -DHAVE_CONFIG_H -DFEAT_GUI_GTK -pthread -I/usr/include/gtk-2.0 -I/usr/lib/gtk-2.0/include -I/usr/include/atk-1.0 -I/usr/include/cairo -I/usr/include/gdk-pixbuf-2.0 -I/usr/include/pango-1.0 -I/usr/include/glib-2.0 -I/usr/lib/glib-2.0/include -I/usr/include/pixman-1 -I/usr/include/freetype2 -I/usr/include/libpng15 -I/usr/local/include -march=x86-64 -mtune=generic -O2 -pipe -fstack-protector --param=ssp-buffer-size=4 -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=1 Linking: gcc -L. -Wl,-O1,--sort-common,--as-needed,-z,relro -rdynamic -Wl,-export-dynamic -Wl,-E -Wl,-rpath,/usr/lib/perl5/core_perl/CORE -Wl,-O1,--sort-common,--as-needed,-z,relro -L/usr/local/lib -Wl,--as-needed -o vim -lgtk-x11-2.0 -lgdk-x11-2.0 -latk-1.0 -lgio-2.0 -lpangoft2-1.0 -lpangocairo-1.0 -lgdk_pixbuf-2.0 -lcairo -lpango-1.0 -lfreetype -lfontconfig -lgobject-2.0 -lglib-2.0 -lSM -lICE -lXt -lX11 -lXdmcp -lSM -lICE -lm -lncurses -lnsl -lacl -lattr -lgpm -ldl -L/usr/lib -llua -Wl,-E -Wl,-rpath,/usr/lib/perl5/core_perl/CORE -Wl,-O1,--sort-common,--as-needed,-z,relro -fstack-protector -L/usr/local/lib -L/usr/lib/perl5/core_perl/CORE -lperl -lnsl -ldl -lm -lcrypt -lutil -lpthread -lc -L/usr/lib/python2.7/config -lpython2.7 -lpthread -ldl -lutil -lm -Xlinker -export-dynamic -lruby -lpthread -lrt -ldl -lcrypt -lm -L/usr/lib Can you tell me how to get my ControlK digraphs work? EDIT: Output of :verbose set enc? fenc? is: encoding=utf-8 Last set from ~/.vimrc fileencoding=

  Read the article

• Helping install mrcwa and solve problems with f2py in Ubuntu 14.04 LTS

  - by user288160

  I am sorry if this is the wrong section but I am starting to get desperate, please someone help me... I need to install the program mrcwa-20080820 (sourceforge.net/projects/mrcwa/) because a summer project that I am involved. I need to use it together with anaconda (store.continuum.io/cshop/anaconda/), I already installed Anaconda and apparently it is working. When I type: conda --version I got the expected answer. conda 3.5.2 If I tried to import numpy or scipy with python or simple type f2py there are no errors. So far so good. But when I tried to install this program sudo python setup.py install I got these errors: running install running build sh: 1: f2py: not found cp: cannot stat ‘mrcwaf.so’: No such file or directory running build_py running install_lib running install_egg_info Removing /usr/local/lib/python2.7/dist-packages/mrcwa-20080820.egg-info Writing /usr/local/lib/python2.7/dist-packages/mrcwa-20080820.egg-info Obs: I am trying to use intel fortran 64-bits and Ubuntu 14.04 LTS. So I was checking f2py and tried to execute the program hello world f2py -c -m hello hello.f from here: cens.ioc.ee/projects/f2py2e/index.html#usage and I had some problems too: running build running config_cc unifing config_cc, config, build_clib, build_ext, build commands --compiler options running config_fc unifing config_fc, config, build_clib, build_ext, build commands --fcompiler options running build_src build_src building extension "hello" sources f2py options: [] f2py:> /tmp/tmpf8P4Y3/src.linux-x86_64-2.7/hellomodule.c creating /tmp/tmpf8P4Y3/src.linux-x86_64-2.7 Reading fortran codes... Reading file 'hello.f' (format:fix,strict) Post-processing... Block: hello Block: foo Post-processing (stage 2)... Building modules... Building module "hello"... Constructing wrapper function "foo"... foo(a) Wrote C/API module "hello" to file "/tmp/tmpf8P4Y3/src.linux-x86_64-2.7 /hellomodule.c" adding '/tmp/tmpf8P4Y3/src.linux-x86_64-2.7/fortranobject.c' to sources. adding '/tmp/tmpf8P4Y3/src.linux-x86_64-2.7' to include_dirs. copying /home/felipe/.local/lib/python2.7/site-packages/numpy/f2py/src/fortranobject.c -> /tmp/tmpf8P4Y3/src.linux-x86_64-2.7 copying /home/felipe/.local/lib/python2.7/site-packages/numpy/f2py/src/fortranobject.h -> /tmp/tmpf8P4Y3/src.linux-x86_64-2.7 build_src: building npy-pkg config files running build_ext customize UnixCCompiler customize UnixCCompiler using build_ext customize Gnu95FCompiler Could not locate executable gfortran Could not locate executable f95 customize IntelFCompiler Found executable /opt/intel/composer_xe_2013_sp1.3.174/bin/intel64/ifort customize LaheyFCompiler Could not locate executable lf95 customize PGroupFCompiler Could not locate executable pgfortran customize AbsoftFCompiler Could not locate executable f90 Could not locate executable f77 customize NAGFCompiler customize VastFCompiler customize CompaqFCompiler Could not locate executable fort customize IntelItaniumFCompiler customize IntelEM64TFCompiler customize IntelEM64TFCompiler customize IntelEM64TFCompiler using build_ext building 'hello' extension compiling C sources C compiler: gcc -pthread -fno-strict-aliasing -g -O2 -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -fPIC creating /tmp/tmpf8P4Y3/tmp creating /tmp/tmpf8P4Y3/tmp/tmpf8P4Y3 creating /tmp/tmpf8P4Y3/tmp/tmpf8P4Y3/src.linux-x86_64-2.7 compile options: '-I/tmp/tmpf8P4Y3/src.linux-x86_64-2.7 -I/home/felipe/.local/lib/python2.7/site-packages/numpy/core/include -I/home/felipe/anaconda/include/python2.7 -c' gcc: /tmp/tmpf8P4Y3/src.linux-x86_64-2.7/hellomodule.c In file included from /home/felipe/.local/lib/python2.7/site-packages/numpy/core/include/numpy/ndarraytypes.h:1761:0, from /home/felipe/.local/lib/python2.7/site-packages/numpy/core/include/numpy/ndarrayobject.h:17, from /home/felipe/.local/lib/python2.7/site-packages/numpy/core/include/numpy/arrayobject.h:4, from /tmp/tmpf8P4Y3/src.linux-x86_64-2.7/fortranobject.h:13, from /tmp/tmpf8P4Y3/src.linux-x86_64-2.7/hellomodule.c:17: /home/felipe/.local/lib/python2.7/site-packages/numpy/core/include/numpy/npy_1_7_deprecated_api.h:15:2: warning: #warning "Using deprecated NumPy API, disable it by " "#defining NPY_NO_DEPRECATED_API NPY_1_7_API_VERSION" [-Wcpp] #warning "Using deprecated NumPy API, disable it by " \ ^ gcc: /tmp/tmpf8P4Y3/src.linux-x86_64-2.7/fortranobject.c In file included from /home/felipe/.local/lib/python2.7/site-packages/numpy/core/include/numpy/ndarraytypes.h:1761:0, from /home/felipe/.local/lib/python2.7/site-packages/numpy/core/include/numpy/ndarrayobject.h:17, from /home/felipe/.local/lib/python2.7/site-packages/numpy/core/include/numpy/arrayobject.h:4, from /tmp/tmpf8P4Y3/src.linux-x86_64-2.7/fortranobject.h:13, from /tmp/tmpf8P4Y3/src.linux-x86_64-2.7/fortranobject.c:2: /home/felipe/.local/lib/python2.7/site-packages/numpy/core/include/numpy/npy_1_7_deprecated_api.h:15:2: warning: #warning "Using deprecated NumPy API, disable it by " "#defining NPY_NO_DEPRECATED_API NPY_1_7_API_VERSION" [-Wcpp] #warning "Using deprecated NumPy API, disable it by " \ ^ compiling Fortran sources Fortran f77 compiler: /opt/intel/composer_xe_2013_sp1.3.174/bin/intel64/ifort -FI -fPIC -xhost -openmp -fp-model strict Fortran f90 compiler: /opt/intel/composer_xe_2013_sp1.3.174/bin/intel64/ifort -FR -fPIC -xhost -openmp -fp-model strict Fortran fix compiler: /opt/intel/composer_xe_2013_sp1.3.174/bin/intel64/ifort -FI -fPIC -xhost -openmp -fp-model strict compile options: '-I/tmp/tmpf8P4Y3/src.linux-x86_64-2.7 -I/home/felipe/.local /lib/python2.7/site-packages/numpy/core/include -I/home/felipe/anaconda/include/python2.7 -c' ifort:f77: hello.f /opt/intel/composer_xe_2013_sp1.3.174/bin/intel64/ifort -shared -shared -nofor_main /tmp/tmpf8P4Y3/tmp/tmpf8P4Y3/src.linux-x86_64-2.7/hellomodule.o /tmp/tmpf8P4Y3 /tmp/tmpf8P4Y3/src.linux-x86_64-2.7/fortranobject.o /tmp/tmpf8P4Y3/hello.o -L/home/felipe /anaconda/lib -lpython2.7 -o ./hello.so Removing build directory /tmp/tmpf8P4Y3 Please help me I am new in ubuntu and python. I really need this program, my advisor is waiting an answer. Thank you very much, Felipe Oliveira.

  Read the article

• Threading across multiple files

  - by Zach M.

  My program is reading in files and using thread to compute the highest prime number, when I put a print statement into the getNum() function my numbers are printing out. However, it seems to just lag no matter how many threads I input. Each file has 1 million integers in it. Does anyone see something apparently wrong with my code? Basically the code is giving each thread 1000 integers to check before assigning a new thread. I am still a C noobie and am just learning the ropes of threading. My code is a mess right now because I have been switching things around constantly. #include <stdio.h> #include <stdlib.h> #include <time.h> #include <string.h> #include <pthread.h> #include <math.h> #include <semaphore.h> //Global variable declaration char *file1 = "primes1.txt"; char *file2 = "primes2.txt"; char *file3 = "primes3.txt"; char *file4 = "primes4.txt"; char *file5 = "primes5.txt"; char *file6 = "primes6.txt"; char *file7 = "primes7.txt"; char *file8 = "primes8.txt"; char *file9 = "primes9.txt"; char *file10 = "primes10.txt"; char **fn; //file name variable int numberOfThreads; int *highestPrime = NULL; int fileArrayNum = 0; int loop = 0; int currentFile = 0; sem_t semAccess; sem_t semAssign; int prime(int n)//check for prime number, return 1 for prime 0 for nonprime { int i; for(i = 2; i <= sqrt(n); i++) if(n % i == 0) return(0); return(1); } int getNum(FILE* file) { int number; char* tempS = malloc(20 *sizeof(char)); fgets(tempS, 20, file); tempS[strlen(tempS)-1] = '\0'; number = atoi(tempS); free(tempS);//free memory for later call return(number); } void* findPrimality(void *threadnum) //main thread function to find primes { int tNum = (int)threadnum; int checkNum; char *inUseFile = NULL; int x=1; FILE* file; while(currentFile < 10){ if(inUseFile == NULL){//inUseFIle being used to check if a file is still being read sem_wait(&semAccess);//critical section inUseFile = fn[currentFile]; sem_post(&semAssign); file = fopen(inUseFile, "r"); while(!feof(file)){ if(x % 1000 == 0 && tNum !=1){ //go for 1000 integers and then wait sem_wait(&semAssign); } checkNum = getNum(file); /* * * * * I think the issue is here * * * */ if(checkNum > highestPrime[tNum]){ if(prime(checkNum)){ highestPrime[tNum] = checkNum; } } x++; } fclose(file); inUseFile = NULL; } currentFile++; } } int main(int argc, char* argv[]) { if(argc != 2){ //checks for number of arguements being passed printf("To many ARGS\n"); return(-1); } else{//Sets thread cound to user input checking for correct number of threads numberOfThreads = atoi(argv[1]); if(numberOfThreads < 1 || numberOfThreads > 10){ printf("To many threads entered\n"); return(-1); } time_t preTime, postTime; //creating time variables int i; fn = malloc(10 * sizeof(char*)); //create file array and initialize fn[0] = file1; fn[1] = file2; fn[2] = file3; fn[3] = file4; fn[4] = file5; fn[5] = file6; fn[6] = file7; fn[7] = file8; fn[8] = file9; fn[9] = file10; sem_init(&semAccess, 0, 1); //initialize semaphores sem_init(&semAssign, 0, numberOfThreads); highestPrime = malloc(numberOfThreads * sizeof(int)); //create an array to store each threads highest number for(loop = 0; loop < numberOfThreads; loop++){//set initial values to 0 highestPrime[loop] = 0; } pthread_t calculationThread[numberOfThreads]; //thread to do the work preTime = time(NULL); //start the clock for(i = 0; i < numberOfThreads; i++){ pthread_create(&calculationThread[i], NULL, findPrimality, (void *)i); } for(i = 0; i < numberOfThreads; i++){ pthread_join(calculationThread[i], NULL); } for(i = 0; i < numberOfThreads; i++){ printf("this is a prime number: %d \n", highestPrime[i]); } postTime= time(NULL); printf("Wall time: %ld seconds\n", (long)(postTime - preTime)); } } Yes I am trying to find the highest number over all. So I have made some head way the last few hours, rescucturing the program as spudd said, currently I am getting a segmentation fault due to my use of structures, I am trying to save the largest individual primes in the struct while giving them the right indices. This is the revised code. So in short what the first thread is doing is creating all the threads and giving them access points to a very large integer array which they will go through and find prime numbers, I want to implement semaphores around the while loop so that while they are executing every 2000 lines or the end they update a global prime number. #include <stdio.h> #include <stdlib.h> #include <time.h> #include <string.h> #include <pthread.h> #include <math.h> #include <semaphore.h> //Global variable declaration char *file1 = "primes1.txt"; char *file2 = "primes2.txt"; char *file3 = "primes3.txt"; char *file4 = "primes4.txt"; char *file5 = "primes5.txt"; char *file6 = "primes6.txt"; char *file7 = "primes7.txt"; char *file8 = "primes8.txt"; char *file9 = "primes9.txt"; char *file10 = "primes10.txt"; int numberOfThreads; int entries[10000000]; int entryIndex = 0; int fileCount = 0; char** fileName; int largestPrimeNumber = 0; //Register functions int prime(int n); int getNum(FILE* file); void* findPrimality(void *threadNum); void* assign(void *num); typedef struct package{ int largestPrime; int startingIndex; int numberCount; }pack; //Beging main code block int main(int argc, char* argv[]) { if(argc != 2){ //checks for number of arguements being passed printf("To many threads!!\n"); return(-1); } else{ //Sets thread cound to user input checking for correct number of threads numberOfThreads = atoi(argv[1]); if(numberOfThreads < 1 || numberOfThreads > 10){ printf("To many threads entered\n"); return(-1); } int threadPointer[numberOfThreads]; //Pointer array to point to entries time_t preTime, postTime; //creating time variables int i; fileName = malloc(10 * sizeof(char*)); //create file array and initialize fileName[0] = file1; fileName[1] = file2; fileName[2] = file3; fileName[3] = file4; fileName[4] = file5; fileName[5] = file6; fileName[6] = file7; fileName[7] = file8; fileName[8] = file9; fileName[9] = file10; FILE* filereader; int currentNum; for(i = 0; i < 10; i++){ filereader = fopen(fileName[i], "r"); while(!feof(filereader)){ char* tempString = malloc(20 *sizeof(char)); fgets(tempString, 20, filereader); tempString[strlen(tempString)-1] = '\0'; entries[entryIndex] = atoi(tempString); entryIndex++; free(tempString); } } //sem_init(&semAccess, 0, 1); //initialize semaphores //sem_init(&semAssign, 0, numberOfThreads); time_t tPre, tPost; pthread_t coordinate; tPre = time(NULL); pthread_create(&coordinate, NULL, assign, (void**)numberOfThreads); pthread_join(coordinate, NULL); tPost = time(NULL); } } void* findPrime(void* pack_array) { pack* currentPack= pack_array; int lp = currentPack->largestPrime; int si = currentPack->startingIndex; int nc = currentPack->numberCount; int i; int j = 0; for(i = si; i < nc; i++){ while(j < 2000 || i == (nc-1)){ if(prime(entries[i])){ if(entries[i] > lp) lp = entries[i]; } j++; } } return (void*)currentPack; } void* assign(void* num) { int y = (int)num; int i; int count = 10000000/y; int finalCount = count + (10000000%y); int sIndex = 0; pack pack_array[(int)num]; pthread_t workers[numberOfThreads]; //thread to do the workers for(i = 0; i < y; i++){ if(i == (y-1)){ pack_array[i].largestPrime = 0; pack_array[i].startingIndex = sIndex; pack_array[i].numberCount = finalCount; } pack_array[i].largestPrime = 0; pack_array[i].startingIndex = sIndex; pack_array[i].numberCount = count; pthread_create(&workers[i], NULL, findPrime, (void *)&pack_array[i]); sIndex += count; } for(i = 0; i< y; i++) pthread_join(workers[i], NULL); } //Functions int prime(int n)//check for prime number, return 1 for prime 0 for nonprime { int i; for(i = 2; i <= sqrt(n); i++) if(n % i == 0) return(0); return(1); }

  Read the article

• How to use c++0x thread in Android NDK?

  - by m-ric

  I am trying to compile this simple program with android-ndk-r8b: jni/hello_jni.cpp #include <iostream> #include <thread> void hello() { std::cout << "Hi i'm a thread!!!" << std::endl; } int main() { std::thread th(hello); th.join(); return 0; } jni/Application.mk APP_OPTIM := release APP_MODULES := hello_thread APP_STL := gnustl_static jni/Android.mk LOCAL_PATH := $(call my-dir) include $(CLEAR_VARS) LOCAL_CPPFLAGS += -std=c++0x -frtti LOCAL_MODULE := hello_thread LOCAL_LDLIBS := -L$(SYSROOT)/usr/lib -pthread LOCAL_SRC_FILES := hello_thread.cpp include $(BUILD_EXECUTABLE) ndk-build returns me an error arguin that 'thread' is not a member of 'std'. I issued ndk-build -n to get the compilation command and issued it alone in my shell: /home/evigier/android-ndk-r8b/toolchains/arm-linux-androideabi-4.6/prebuilt/linux-x86/bin/arm-linux-androideabi-g++ -MMD -MP -MF /home/evigier/eclipse_workspace/hello_thread/obj/local/armeabi/objs/hello_thread/hello_thread.o.d -fpic -ffunction-sections -funwind-tables -fstack-protector -D__ARM_ARCH_5__ -D__ARM_ARCH_5T__ -D__ARM_ARCH_5E__ -D__ARM_ARCH_5TE__ -march=armv5te -mtune=xscale -msoft-float -fno-exceptions -fno-rtti -mthumb -Os -fomit-frame-pointer -fno-strict-aliasing -finline-limit=64 -I/home/evigier/android-ndk-r8b/sources/cxx-stl/gnu-libstdc++/4.6/include -I/home/evigier/android-ndk-r8b/sources/cxx-stl/gnu-libstdc++/4.6/libs/armeabi/include -I/home/evigier/eclipse_workspace/hello_thread/jni -DANDROID -Wa,--noexecstack -std=c++0x -frtti -O2 -DNDEBUG -g -I/home/evigier/android-ndk-r8b/platforms/android-14/arch-arm/usr/include -c /home/evigier/eclipse_workspace/hello_thread/jni/hello_thread.cpp -o /home/evigier/eclipse_workspace/hello_thread/obj/local/armeabi/objs/hello_thread/hello_thread.o Compile++ thumb : hello_thread <= hello_thread.cpp In file included from /home/evigier/android-ndk-r8b/platforms/android-14/arch-arm/usr/include/stdio.h:55:0, from /home/evigier/android-ndk-r8b/platforms/android-14/arch-arm/usr/include/wchar.h:33, from /home/evigier/android-ndk-r8b/sources/cxx-stl/gnu-libstdc++/4.6/include/cwchar:46, from /home/evigier/android-ndk-r8b/sources/cxx-stl/gnu-libstdc++/4.6/include/bits/postypes.h:42, from /home/evigier/android-ndk-r8b/sources/cxx-stl/gnu-libstdc++/4.6/include/iosfwd:42, from /home/evigier/android-ndk-r8b/sources/cxx-stl/gnu-libstdc++/4.6/include/ios:39, from /home/evigier/android-ndk-r8b/sources/cxx-stl/gnu-libstdc++/4.6/include/ostream:40, from /home/evigier/android-ndk-r8b/sources/cxx-stl/gnu-libstdc++/4.6/include/iostream:40, from jni/hello_thread.cpp:4: /home/evigier/android-ndk-r8b/platforms/android-14/arch-arm/usr/include/sys/types.h:124:9: error: 'uint64_t' does not name a type /home/evigier/eclipse_workspace/hello_thread/jni/hello_thread.cpp: In function 'int main()': /home/evigier/eclipse_workspace/hello_thread/jni/hello_thread.cpp:14:5: error: 'thread' is not a member of 'std' /home/evigier/eclipse_workspace/hello_thread/jni/hello_thread.cpp:14:17: error: expected ';' before 'th' /home/evigier/eclipse_workspace/hello_thread/jni/hello_thread.cpp:15:5: error: 'th' was not declared in this scope I read a lot of threads/questions about POSIX threads and C++ threads, but still cannot find my answer. My arm-linux-androideabi/include/c++/4.6/thread file defines class thread in std only: #if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1) They don't seem to be defined in my sdk (c++config.h). But how can I possibly turn them on safely? Do i need to compile my own toolchain to use (non-p)threads? My host computer is : Linux evigier-ThinkPad-X220 3.0.0-17-generic #30-Ubuntu SMP Thu Mar 8 20:45:39 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux

  Read the article

• pthreads_setaffinity_np: Invalid argument?

  - by hahuang65

  I've managed to get my pthreads program sort of working. Basically I am trying to manually set the affinity of 4 threads such that thread 1 runs on CPU 1, thread 2 runs on CPU 2, thread 3 runs on CPU 3, and thread 4 runs on CPU 4. After compiling, my code works for a few threads but not others (seems like thread 1 never works) but running the same compiled program a couple of different times gives me different results. For example: hao@Gorax:~/Desktop$ ./a.out Thread 3 is running on CPU 3 pthread_setaffinity_np: Invalid argument Thread Thread 2 is running on CPU 2 hao@Gorax:~/Desktop$ ./a.out Thread 2 is running on CPU 2 pthread_setaffinity_np: Invalid argument pthread_setaffinity_np: Invalid argument Thread 3 is running on CPU 3 Thread 3 is running on CPU 3 hao@Gorax:~/Desktop$ ./a.out Thread 2 is running on CPU 2 pthread_setaffinity_np: Invalid argument Thread 4 is running on CPU 4 Thread 4 is running on CPU 4 hao@Gorax:~/Desktop$ ./a.out pthread_setaffinity_np: Invalid argument My question is "Why does this happen? Also, why does the message sometimes print twice?" Here is the code: #define _GNU_SOURCE #include <stdio.h> #include <pthread.h> #include <stdlib.h> #include <sched.h> #include <errno.h> #define handle_error_en(en, msg) \ do { errno = en; perror(msg); exit(EXIT_FAILURE); } while (0) void *thread_function(char *message) { int s, j, number; pthread_t thread; cpu_set_t cpuset; number = (int)message; thread = pthread_self(); CPU_SET(number, &cpuset); s = pthread_setaffinity_np(thread, sizeof(cpu_set_t), &cpuset); if (s != 0) { handle_error_en(s, "pthread_setaffinity_np"); } printf("Thread %d is running on CPU %d\n", number, sched_getcpu()); exit(EXIT_SUCCESS); } int main() { pthread_t thread1, thread2, thread3, thread4; int thread1Num = 1; int thread2Num = 2; int thread3Num = 3; int thread4Num = 4; int thread1Create, thread2Create, thread3Create, thread4Create, i, temp; thread1Create = pthread_create(&thread1, NULL, (void *)thread_function, (char *)thread1Num); thread2Create = pthread_create(&thread2, NULL, (void *)thread_function, (char *)thread2Num); thread3Create = pthread_create(&thread3, NULL, (void *)thread_function, (char *)thread3Num); thread4Create = pthread_create(&thread4, NULL, (void *)thread_function, (char *)thread4Num); pthread_join(thread1, NULL); pthread_join(thread2, NULL); pthread_join(thread3, NULL); pthread_join(thread4, NULL); return 0; }

  Read the article

• About fork system call and global variables

  - by lurks

  I have this program in C++ that forks two new processes: #include <pthread.h> #include <iostream> #include <unistd.h> #include <sys/types.h> #include <sys/wait.h> #include <cstdlib> using namespace std; int shared; void func(){ extern int shared; for (int i=0; i<10;i++) shared++; cout<<"Process "<<getpid()<<", shared " <<shared<<", &shared " <<&shared<<endl; } int main(){ extern int shared; pid_t p1,p2; int status; shared=0; if ((p1=fork())==0) {func();exit(0);}; if ((p2=fork())==0) {func();exit(0);}; for(int i=0;i<10;i++) shared++; waitpid(p1,&status,0); waitpid(p2,&status,0);; cout<<"shared variable is: "<<shared<<endl; cout<<"Process "<<getpid()<<", shared " <<shared<<", &shared " <<&shared<<endl; } The two forked processes make an increment on the shared variables and the parent process does the same. As the variable belongs to the data segment of each process, the final value is 10 because the increment is independent. However, the memory address of the shared variables is the same, you can try compiling and watching the output of the program. How can that be explained ? I cannot understand that, I thought I knew how the fork() works, but this seems very odd.. I need an explanation on why the address is the same, although they are separate variables.

  Read the article

• passing pipe to threads

  - by alaamh

  I see it's easy to open pipe between two process using fork, but how we can passing open pipe to threads. Assume we need to pass out of PROGRAM A to PROGRAM B "may by more than one thread", PROGRAM B send his output to PROGRAM C #include <stdio.h> #include <stdlib.h> #include <pthread.h> struct targ_s { int fd_reader; }; void *thread1(void *arg) { struct targ_s *targ = (struct targ_s*) arg; int status, fd[2]; pid_t pid; pipe(fd); pid = fork(); if (pid == 0) { dup2(STDIN_FILENO, targ->fd_reader); close(fd[0]); dup2(fd[1], STDOUT_FILENO); close(fd[1]); execvp ("PROGRAM B", NULL); exit(1); } else { close(fd[1]); dup2(fd[0], STDIN_FILENO); close(fd[0]); execl("PROGRAM C", NULL); wait(&status); return NULL; } } int main(void) { FILE *fpipe; char *command = "PROGRAM A"; char buffer[1024]; if (!(fpipe = (FILE*) popen(command, "r"))) { perror("Problems with pipe"); exit(1); } char* outfile = "out.dat"; FILE* f = fopen (outfile, "wb"); int fd = fileno( f ); struct targ_s targ; targ.fd_reader = fd; pthread_t thid; if (pthread_create(&thid, NULL, thread1, &targ) != 0) { perror("pthread_create() error"); exit(1); } int len; while (read(fpipe, buffer, sizeof (buffer)) != 0) { len = strlen(buffer); write(fd, buffer, len); } pclose(fpipe); return (0); }

  Read the article

• problem with fifos linux

  - by nunos

  I am having problem debugging why n_bytes in read_from_fifo function in client.c doesn't correspond to the value written to the fifo. It should only write 25 bytes but it tries to read a lot more (1836020505 bytes (!) to be exact). Any idea why this is happening? server.c: #include <stdio.h> #include <stdlib.h> #include <string.h> #include <errno.h> #include <unistd.h> #include <fcntl.h> #include <sys/wait.h> #include <signal.h> #include <pthread.h> #include <sys/stat.h> typedef enum { false, true } bool; //first read the int with the number of bytes the data will have //then read that number of bytes bool read_from_fifo(int fd, char* var) { int n_bytes; if (read(fd, &n_bytes, sizeof(int))) { printf("going to read %d bytes\n", n_bytes); if (read(fd, var, n_bytes)) printf("read var\n"); else { printf("error in read var. errno: %d\n", errno); exit(-1); } } return true; } int main() { mkfifo("/tmp/foo", 0660); int fd = open("/tmp/foo", O_RDONLY); char var[100]; read_from_fifo(fd, var); printf("var: %s\n", var); return 0; } client.c: #include <stdio.h> #include <stdlib.h> #include <string.h> #include <errno.h> #include <unistd.h> #include <fcntl.h> typedef enum { false, true } bool; //first write to fd a int with the number of bytes that will be written afterwards bool write_to_fifo(int fd, char* data) { int n_bytes = (strlen(data)) * sizeof(char); printf("going to write %d bytes\n", n_bytes); if (write(fd, &n_bytes, sizeof(int) != -1)) if (write(fd, data, n_bytes) != -1) return true; return false; } int main() { int fd = open("/tmp/foo", O_WRONLY); char data[] = "some random string abcdef"; write_to_fifo(fd, data); return 0; } Help is greatly appreciated. Thanks in advance.

  Read the article

• Permanent mutex locking causing deadlock?

  - by Daniel

  I am having a problem with mutexes (pthread_mutex on Linux) where if a thread locks a mutex right again after unlocking it, another thread is not very successful getting a lock. I've attached test code where one mutex is created, along with two threads that in an endless loop lock the mutex, sleep for a while and unlock it again. The output I expect to see is "alive" messages from both threads, one from each (e.g. 121212121212. However what I get is that one threads gets the majority of locks (e.g. 111111222222222111111111 or just 1111111111111...). If I add a usleep(1) after the unlocking, everything works as expected. Apparently when the thread goes to SLEEP the other thread gets its lock - however this is not the way I was expecting it, as the other thread has already called pthread_mutex_lock. I suspect this is the way this is implemented, in that the actice thread has priority, however it causes certain problem in this particular testcase. Is there any way to prevent it (short of adding a deliberately large enough delay or some kind of signaling) or where is my error in understanding? #include <pthread.h> #include <stdio.h> #include <string.h> #include <sys/time.h> #include <unistd.h> pthread_mutex_t mutex; void* threadFunction(void *id) { int count=0; while(true) { pthread_mutex_lock(&mutex); usleep(50*1000); pthread_mutex_unlock(&mutex); // usleep(1); ++count; if (count % 10 == 0) { printf("Thread %d alive\n", *(int*)id); count = 0; } } return 0; } int main() { // create one mutex pthread_mutexattr_t attr; pthread_mutexattr_init(&attr); pthread_mutex_init(&mutex, &attr); // create two threads pthread_t thread1; pthread_t thread2; pthread_attr_t attributes; pthread_attr_init(&attributes); int id1 = 1, id2 = 2; pthread_create(&thread1, &attributes, &threadFunction, &id1); pthread_create(&thread2, &attributes, &threadFunction, &id2); pthread_attr_destroy(&attributes); sleep(1000); return 0; }

  Read the article

• Multi-threaded random_r is slower than single threaded version.

  - by Nixuz

  The following program is essentially the same the one described here. When I run and compile the program using two threads (NTHREADS == 2), I get the following run times: real 0m14.120s user 0m25.570s sys 0m0.050s When it is run with just one thread (NTHREADS == 1), I get run times significantly better even though it is only using one core. real 0m4.705s user 0m4.660s sys 0m0.010s My system is dual core, and I know random_r is thread safe and I am pretty sure it is non-blocking. When the same program is run without random_r and a calculation of cosines and sines is used as a replacement, the dual-threaded version runs in about 1/2 the time as expected. #include <pthread.h> #include <stdlib.h> #include <stdio.h> #define NTHREADS 2 #define PRNG_BUFSZ 8 #define ITERATIONS 1000000000 void* thread_run(void* arg) { int r1, i, totalIterations = ITERATIONS / NTHREADS; for (i = 0; i < totalIterations; i++){ random_r((struct random_data*)arg, &r1); } printf("%i\n", r1); } int main(int argc, char** argv) { struct random_data* rand_states = (struct random_data*)calloc(NTHREADS, sizeof(struct random_data)); char* rand_statebufs = (char*)calloc(NTHREADS, PRNG_BUFSZ); pthread_t* thread_ids; int t = 0; thread_ids = (pthread_t*)calloc(NTHREADS, sizeof(pthread_t)); /* create threads */ for (t = 0; t < NTHREADS; t++) { initstate_r(random(), &rand_statebufs[t], PRNG_BUFSZ, &rand_states[t]); pthread_create(&thread_ids[t], NULL, &thread_run, &rand_states[t]); } for (t = 0; t < NTHREADS; t++) { pthread_join(thread_ids[t], NULL); } free(thread_ids); free(rand_states); free(rand_statebufs); } I am confused why when generating random numbers the two threaded version performs much worse than the single threaded version, considering random_r is meant to be used in multi-threaded applications.

  Read the article

• Thread feeding other MultiThreading

  - by alaamh

  I see it's easy to open pipe between two process using fork, but how we can passing open pipe to threads. Assume we need to pass out of PROGRAM A to PROGRAM B "may by more than one thread", PROGRAM B send his output to PROGRAM C #include <stdio.h> #include <stdlib.h> #include <pthread.h> struct targ_s { char* reader; }; void *thread1(void *arg) { struct targ_s *targ = (struct targ_s*) arg; int status, fd[2]; pid_t pid; pipe(fd); pid = fork(); if (pid == 0) { int fd = fileno( targ->fd_reader ); dup2(STDIN_FILENO, fd); close(fd[0]); dup2(fd[1], STDOUT_FILENO); close(fd[1]); execvp ("PROGRAM B", NULL); exit(1); } else { close(fd[1]); dup2(fd[0], STDIN_FILENO); close(fd[0]); execl("PROGRAM C", NULL); wait(&status); return NULL; } } int main(void) { FILE *fpipe; char *command = "PROGRAM A"; char buffer[1024]; if (!(fpipe = (FILE*) popen(command, "r"))) { perror("Problems with pipe"); exit(1); } char* outfile = "out.dat"; FILE* f = fopen (outfile, "wb"); int fd = fileno( f ); struct targ_s targ; targ.fd_reader = outfile; pthread_t thid; if (pthread_create(&thid, NULL, thread1, &targ) != 0) { perror("pthread_create() error"); exit(1); } int len; while (read(fpipe, buffer, sizeof (buffer)) != 0) { len = strlen(buffer); write(fd, buffer, len); } pclose(fpipe); return (0); }

  Read the article

• How do I install PyYAML into local install of Python?

  - by Daryl Spitzer

  I've installed Python 2.6.4 into (a subdirectory in) my home directory on a Linux machine with Python 2.3.4 pre-installed, because I need to run some code that I've decided would require too much work to make it run on 2.3.4. (I'm not on the sudoers list for that machine.) I was hoping I could run ~/Python-2.6.4/python setup.py install (from the PyYAML directory in my home directory, where I untarred the PyYAML sources) and it would be smart enough to install it into my local Python 2.6.4 install. But it's not. (See the P.S.) Is it possible to install PyYAML into my local Python install, so that "import yaml" will work when I invoke that Python? If so, how do I do that? P.S. Here's the output when I ran ~/Python-2.6.4/python setup.py install: running install running build running build_py creating build/lib.linux-ppc64-2.6 creating build/lib.linux-ppc64-2.6/yaml copying lib/yaml/composer.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/nodes.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/dumper.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/resolver.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/events.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/emitter.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/error.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/loader.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/cyaml.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/scanner.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/__init__.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/serializer.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/reader.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/representer.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/constructor.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/tokens.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/parser.py -> build/lib.linux-ppc64-2.6/yaml running build_ext creating build/temp.linux-ppc64-2.6 checking if libyaml is compilable gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -fPIC -I/home/dspitzer/Python-2.6.4/Include -I/home/dspitzer/Python-2.6.4 -c build/temp.linux-ppc64-2.6/check_libyaml.c -o build/temp.linux-ppc64-2.6/check_libyaml.o build/temp.linux-ppc64-2.6/check_libyaml.c:2:18: yaml.h: No such file or directory build/temp.linux-ppc64-2.6/check_libyaml.c: In function `main': build/temp.linux-ppc64-2.6/check_libyaml.c:5: error: `yaml_parser_t' undeclared (first use in this function) build/temp.linux-ppc64-2.6/check_libyaml.c:5: error: (Each undeclared identifier is reported only once build/temp.linux-ppc64-2.6/check_libyaml.c:5: error: for each function it appears in.) build/temp.linux-ppc64-2.6/check_libyaml.c:5: error: syntax error before "parser" build/temp.linux-ppc64-2.6/check_libyaml.c:6: error: `yaml_emitter_t' undeclared (first use in this function) build/temp.linux-ppc64-2.6/check_libyaml.c:8: warning: implicit declaration of function `yaml_parser_initialize' build/temp.linux-ppc64-2.6/check_libyaml.c:8: error: `parser' undeclared (first use in this function) build/temp.linux-ppc64-2.6/check_libyaml.c:9: warning: implicit declaration of function `yaml_parser_delete' build/temp.linux-ppc64-2.6/check_libyaml.c:11: warning: implicit declaration of function `yaml_emitter_initialize' build/temp.linux-ppc64-2.6/check_libyaml.c:11: error: `emitter' undeclared (first use in this function) build/temp.linux-ppc64-2.6/check_libyaml.c:12: warning: implicit declaration of function `yaml_emitter_delete' libyaml is not found or a compiler error: forcing --without-libyaml (if libyaml is installed correctly, you may need to specify the option --include-dirs or uncomment and modify the parameter include_dirs in setup.cfg) running install_lib creating /usr/local/lib/python2.6 error: could not create '/usr/local/lib/python2.6': Permission denied

  Read the article

• OS X 10.9 Mavericks Kernel Panics out of the box

  - by Kevin

  OS X Kernel panics after a fresh install of OS X 10.9 on a 17" Macbook Pro. Anonymous UUID: D002464D-24B7-C2B5-3D83-1C0B02873B29 Wed Oct 30 11:08:17 2013 panic(cpu 1 caller 0xffffff8006edc19e): Kernel trap at 0xffffff7f88e0a96c, type 14=page fault, registers: CR0: 0x000000008001003b, CR2: 0xffffef7f88e309b8, CR3: 0x0000000009c2d000, CR4: 0x0000000000000660 RAX: 0x0fffffd0c7b30000, RBX: 0xffffef7f88e309b0, RCX: 0x0000000000000001, RDX: 0x000002f384d06471 RSP: 0xffffff80eff03d80, RBP: 0xffffff80eff03e70, RSI: 0x0000031384cfb168, RDI: 0xffffff80e8f05148 R8: 0xffffff801b0f8670, R9: 0x0000000000000005, R10: 0x0000000000004a24, R11: 0x0000000000000202 R12: 0xffffff801938b800, R13: 0x0000000000000005, R14: 0xffffff80e8f05148, R15: 0xffffff7f88e2ee20 RFL: 0x0000000000010006, RIP: 0xffffff7f88e0a96c, CS: 0x0000000000000008, SS: 0x0000000000000010 Fault CR2: 0xffffef7f88e309b8, Error code: 0x0000000000000002, Fault CPU: 0x1 Backtrace (CPU 1), Frame : Return Address 0xffffff80eff03a10 : 0xffffff8006e22f69 0xffffff80eff03a90 : 0xffffff8006edc19e 0xffffff80eff03c60 : 0xffffff8006ef3606 0xffffff80eff03c80 : 0xffffff7f88e0a96c 0xffffff80eff03e70 : 0xffffff7f88e09b89 0xffffff80eff03f30 : 0xffffff8006edda5c 0xffffff80eff03f50 : 0xffffff8006e3757a 0xffffff80eff03f90 : 0xffffff8006e378c8 0xffffff80eff03fb0 : 0xffffff8006ed6aa7 Kernel Extensions in backtrace: com.apple.driver.AppleIntelCPUPowerManagement(216.0)[A6EE4D7B-228E-3A3C-95BA-10ED6F331236]@0xffffff7f88e07000->0xffffff7f88e31fff BSD process name corresponding to current thread: kernel_task Mac OS version: 13A603 Kernel version: Darwin Kernel Version 13.0.0: Thu Sep 19 22:22:27 PDT 2013; root:xnu-2422.1.72~6/RELEASE_X86_64 Kernel UUID: 1D9369E3-D0A5-31B6-8D16-BFFBBB390393 Kernel slide: 0x0000000006c00000 Kernel text base: 0xffffff8006e00000 System model name: MacBookPro5,2 (Mac-F2268EC8) System uptime in nanoseconds: 4634353513870 last loaded kext at 39203945245: com.viscosityvpn.Viscosity.tun 1.0 (addr 0xffffff7f89200000, size 32768) last unloaded kext at 147930318702: com.apple.driver.AppleFileSystemDriver 3.0.1 (addr 0xffffff7f89110000, size 8192) loaded kexts: com.viscosityvpn.Viscosity.tun 1.0 com.viscosityvpn.Viscosity.tap 1.0 com.apple.driver.AudioAUUC 1.60 com.apple.driver.AppleHWSensor 1.9.5d0 com.apple.filesystems.autofs 3.0 com.apple.iokit.IOBluetoothSerialManager 4.2.0f6 com.apple.driver.AGPM 100.14.11 com.apple.driver.AppleMikeyHIDDriver 124 com.apple.driver.AppleHDA 2.5.2fc2 com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport 4.2.0f6 com.apple.GeForceTesla 8.1.8 com.apple.driver.AppleMikeyDriver 2.5.2fc2 com.apple.iokit.IOUserEthernet 1.0.0d1 com.apple.driver.AppleUpstreamUserClient 3.5.13 com.apple.driver.AppleMuxControl 3.4.12 com.apple.driver.ACPI_SMC_PlatformPlugin 1.0.0 com.apple.driver.AppleSMCLMU 2.0.4d1 com.apple.Dont_Steal_Mac_OS_X 7.0.0 com.apple.driver.AppleHWAccess 1 com.apple.driver.AppleMCCSControl 1.1.12 com.apple.driver.AppleLPC 1.7.0 com.apple.driver.SMCMotionSensor 3.0.4d1 com.apple.driver.AppleUSBTCButtons 240.2 com.apple.driver.AppleUSBTCKeyboard 240.2 com.apple.driver.AppleIRController 325.7 com.apple.AppleFSCompression.AppleFSCompressionTypeDataless 1.0.0d1 com.apple.AppleFSCompression.AppleFSCompressionTypeZlib 1.0.0d1 com.apple.BootCache 35 com.apple.iokit.SCSITaskUserClient 3.6.0 com.apple.driver.XsanFilter 404 com.apple.iokit.IOAHCIBlockStorage 2.4.0 com.apple.driver.AppleUSBHub 650.4.4 com.apple.driver.AppleUSBEHCI 650.4.1 com.apple.driver.AppleFWOHCI 4.9.9 com.apple.driver.AirPort.Brcm4331 700.20.22 com.apple.driver.AppleAHCIPort 2.9.5 com.apple.nvenet 2.0.21 com.apple.driver.AppleUSBOHCI 650.4.1 com.apple.driver.AppleSmartBatteryManager 161.0.0 com.apple.driver.AppleRTC 2.0 com.apple.driver.AppleHPET 1.8 com.apple.driver.AppleACPIButtons 2.0 com.apple.driver.AppleSMBIOS 2.0 com.apple.driver.AppleACPIEC 2.0 com.apple.driver.AppleAPIC 1.7 com.apple.driver.AppleIntelCPUPowerManagementClient 216.0.0 com.apple.nke.applicationfirewall 153 com.apple.security.quarantine 3 com.apple.driver.AppleIntelCPUPowerManagement 216.0.0 com.apple.kext.triggers 1.0 com.apple.iokit.IOSerialFamily 10.0.7 com.apple.AppleGraphicsDeviceControl 3.4.12 com.apple.driver.DspFuncLib 2.5.2fc2 com.apple.vecLib.kext 1.0.0 com.apple.iokit.IOAudioFamily 1.9.4fc11 com.apple.kext.OSvKernDSPLib 1.14 com.apple.iokit.IOBluetoothHostControllerUSBTransport 4.2.0f6 com.apple.iokit.IOSurface 91 com.apple.iokit.IOBluetoothFamily 4.2.0f6 com.apple.nvidia.classic.NVDANV50HalTesla 8.1.8 com.apple.driver.AppleSMBusPCI 1.0.12d1 com.apple.driver.AppleGraphicsControl 3.4.12 com.apple.driver.IOPlatformPluginLegacy 1.0.0 com.apple.driver.AppleBacklightExpert 1.0.4 com.apple.iokit.IOFireWireIP 2.2.5 com.apple.driver.AppleHDAController 2.5.2fc2 com.apple.iokit.IOHDAFamily 2.5.2fc2 com.apple.driver.AppleSMBusController 1.0.11d1 com.apple.nvidia.classic.NVDAResmanTesla 8.1.8 com.apple.driver.IOPlatformPluginFamily 5.5.1d27 com.apple.iokit.IONDRVSupport 2.3.6 com.apple.iokit.IOGraphicsFamily 2.3.6 com.apple.driver.AppleSMC 3.1.6d1 com.apple.driver.AppleUSBMultitouch 240.6 com.apple.iokit.IOUSBHIDDriver 650.4.4 com.apple.driver.AppleUSBMergeNub 650.4.0 com.apple.driver.AppleUSBComposite 650.4.0 com.apple.driver.CoreStorage 380 com.apple.iokit.IOSCSIMultimediaCommandsDevice 3.6.0 com.apple.iokit.IOBDStorageFamily 1.7 com.apple.iokit.IODVDStorageFamily 1.7.1 com.apple.iokit.IOCDStorageFamily 1.7.1 com.apple.iokit.IOAHCISerialATAPI 2.6.0 com.apple.iokit.IOSCSIArchitectureModelFamily 3.6.0 com.apple.iokit.IOUSBUserClient 650.4.4 com.apple.iokit.IOFireWireFamily 4.5.5 com.apple.iokit.IO80211Family 600.34 com.apple.iokit.IOAHCIFamily 2.6.0 com.apple.iokit.IONetworkingFamily 3.2 com.apple.iokit.IOUSBFamily 650.4.4 com.apple.driver.NVSMU 2.2.9 com.apple.driver.AppleEFINVRAM 2.0 com.apple.driver.AppleEFIRuntime 2.0 com.apple.iokit.IOHIDFamily 2.0.0 com.apple.iokit.IOSMBusFamily 1.1 com.apple.security.sandbox 278.10 com.apple.kext.AppleMatch 1.0.0d1 com.apple.security.TMSafetyNet 7 com.apple.driver.AppleKeyStore 2 com.apple.driver.DiskImages 371.1 com.apple.iokit.IOStorageFamily 1.9 com.apple.iokit.IOReportFamily 21 com.apple.driver.AppleFDEKeyStore 28.30 com.apple.driver.AppleACPIPlatform 2.0 com.apple.iokit.IOPCIFamily 2.8 com.apple.iokit.IOACPIFamily 1.4 com.apple.kec.pthread 1 com.apple.kec.corecrypto 1.0 System Profile: Model: MacBookPro5,2, BootROM MBP52.008E.B05, 2 processors, Intel Core 2 Duo, 2.8 GHz, 8 GB, SMC 1.42f4 Graphics: NVIDIA GeForce 9400M, NVIDIA GeForce 9400M, PCI, 256 MB Graphics: NVIDIA GeForce 9600M GT, NVIDIA GeForce 9600M GT, PCIe, 512 MB Memory Module: BANK 0/DIMM0, 4 GB, DDR3, 1333 MHz, 0x04CD, 0x46332D3130363636434C392D344742535100 Memory Module: BANK 1/DIMM0, 4 GB, DDR3, 1333 MHz, 0x04CD, 0x46332D3130363636434C392D344742535100 AirPort: spairport_wireless_card_type_airport_extreme (0x14E4, 0x8D), Broadcom BCM43xx 1.0 (5.106.98.100.22) Bluetooth: Version 4.2.0f6 12982, 3 services, 15 devices, 1 incoming serial ports Network Service: Wi-Fi, AirPort, en1 Serial ATA Device: Samsung SSD 840 Series, 120.03 GB Serial ATA Device: MATSHITADVD-R UJ-868 USB Device: Built-in iSight USB Device: BRCM2046 Hub USB Device: Bluetooth USB Host Controller USB Device: Apple Internal Keyboard / Trackpad USB Device: IR Receiver Thunderbolt Bus:

  Read the article

• php crashes with no core file and this message : apc_mmap failed

  - by greg0ire

  Description of the problem Regularly, cron php processes crash on our production server, which result in mails with the following body : PHP Fatal error: PHP Startup: apc_mmap: mmap failed: in Unknown on line 0 Segmentation fault (core dumped) I think the Segmentation fault (core dumped) should result in core files being handled by apport and then written in /var/crashes, but the files I can see there are there since yesterday, although the last crash occured today : -rw-r----- 1 root whoopsie 1138528 mai 22 04:09 _usr_bin_php5.0.crash -rw-r----- 1 frontoffice whoopsie 1166373 mai 20 18:00 _usr_bin_php5.1005.crash -rw-r----- 1 frontoffice whoopsie 81622658 mai 22 00:05 _usr_sbin_php5-fpm.1005.crash I tried to download the last one anyway, and ran gdb /usr/sbin/php5-fpm /tmp/_usr_sbin_php5-fpm.1005.crash, only to be told that the file is not a core file (its format was not recognized). Here is the server's apc configuration : cat /etc/php5/cli/conf.d/20-apc.ini extension=apc.so apc.shm_size=512M apc.ttl=3600 apc.user_ttl=3600 apc.enable_cli=1 I'm mostly worried about the apc.shm_size… isn't it too high or too low ? I understand it has to do with the size of memory segments. Question(s) What could be the problem ? How can I troubleshoot it (how can I get a valid core file ?) ? System information free total used free shared buffers cached Mem: 5081296 4354684 726612 0 374744 959968 -/+ buffers/cache: 3019972 2061324 Swap: 522236 516888 5348 cat /etc/lsb-release DISTRIB_ID=Ubuntu DISTRIB_RELEASE=12.04 DISTRIB_CODENAME=precise DISTRIB_DESCRIPTION="Ubuntu 12.04.2 LTS" php -v PHP 5.4.17-1~precise+1 (cli) (built: Jul 17 2013 18:14:06) Copyright (c) 1997-2013 The PHP Group Zend Engine v2.4.0, Copyright (c) 1998-2013 Zend Technologies php -i excerpt : Configuration apc APC Support => enabled Version => 3.1.13 APC Debugging => Disabled MMAP Support => Enabled MMAP File Mask => Locking type => pthread mutex Locks Serialization Support => php Revision => $Revision: 327136 $ Build Date => Nov 20 2012 18:41:36 Directive => Local Value => Master Value apc.cache_by_default => On => On apc.canonicalize => On => On apc.coredump_unmap => Off => Off apc.enable_cli => On => On apc.enabled => On => On apc.file_md5 => Off => Off apc.file_update_protection => 2 => 2 apc.filters => no value => no value apc.gc_ttl => 3600 => 3600 apc.include_once_override => Off => Off apc.lazy_classes => Off => Off apc.lazy_functions => Off => Off apc.max_file_size => 1M => 1M apc.mmap_file_mask => no value => no value apc.num_files_hint => 1000 => 1000 apc.preload_path => no value => no value apc.report_autofilter => Off => Off apc.rfc1867 => Off => Off apc.rfc1867_freq => 0 => 0 apc.rfc1867_name => APC_UPLOAD_PROGRESS => APC_UPLOAD_PROGRESS apc.rfc1867_prefix => upload_ => upload_ apc.rfc1867_ttl => 3600 => 3600 apc.serializer => default => default apc.shm_segments => 1 => 1 apc.shm_size => 512M => 512M apc.shm_strings_buffer => 4M => 4M apc.slam_defense => On => On apc.stat => On => On apc.stat_ctime => Off => Off apc.ttl => 3600 => 3600 apc.use_request_time => On => On apc.user_entries_hint => 4096 => 4096 apc.user_ttl => 3600 => 3600 apc.write_lock => On => On php -m [PHP Modules] apc bcmath bz2 calendar Core ctype curl date dba dom ereg exif fileinfo filter ftp gd gettext hash iconv imagick intl json ldap libxml mbstring memcache memcached mhash mysql mysqli openssl pcntl pcre PDO pdo_mysql pdo_pgsql pdo_sqlite pgsql Phar posix Reflection session shmop SimpleXML soap sockets SPL sqlite3 standard sysvmsg sysvsem sysvshm tidy tokenizer wddx xml xmlreader xmlwriter zip zlib [Zend Modules] ulimit -a core file size (blocks, -c) 0 data seg size (kbytes, -d) unlimited scheduling priority (-e) 0 file size (blocks, -f) unlimited pending signals (-i) 39531 max locked memory (kbytes, -l) 64 max memory size (kbytes, -m) unlimited open files (-n) 1024 pipe size (512 bytes, -p) 8 POSIX message queues (bytes, -q) 819200 real-time priority (-r) 0 stack size (kbytes, -s) 8192 cpu time (seconds, -t) unlimited max user processes (-u) 39531 virtual memory (kbytes, -v) unlimited file locks (-x) unlimited

  Read the article

• Confusion related to sigwait in multiprocess system

  - by user34790

  I am having difficulty in understanding IPC in multiprocess system. I have this system where there are three child processes that send two types of signals to their process group. There are four types of signal handling processes responsible for a particular type of signal. There is this monitoring process which waits for both the signals and then processes accordingly. When I run this program for a while, the monitoring process doesn't seem to pick up the signal as well as the signal handling process. I could see in the log that the signal is only being generated but not handled at all. My code is given below #include <cstdlib> #include <iostream> #include <iomanip> #include <unistd.h> #include <sys/types.h> #include <sys/wait.h> #include <sys/time.h> #include <signal.h> #include <unistd.h> #include <fcntl.h> #include <cstdio> #include <stdlib.h> #include <stdio.h> #include <pthread.h> using namespace std; double timestamp() { struct timeval tp; gettimeofday(&tp, NULL); return (double)tp.tv_sec + tp.tv_usec / 1000000.; } double getinterval() { srand(time(NULL)); int r = rand()%10 + 1; double s = (double)r/100; } int count; int count_1; int count_2; double time_1[10]; double time_2[10]; pid_t senders[1]; pid_t handlers[4]; pid_t reporter; void catcher(int sig) { printf("Signal catcher called for %d",sig); } int main(int argc, char *argv[]) { void signal_catcher_int(int); pid_t pid,w; int status; if(signal(SIGUSR1, SIG_IGN) == SIG_ERR) { perror("1"); return 1; } if(signal(SIGUSR2 ,SIG_IGN) == SIG_ERR) { perror("2"); return 2; } if(signal(SIGINT,signal_catcher_int) == SIG_ERR) { perror("3"); return 2; } //Registering the signal handler for(int i=0; i<4; i++) { if((pid = fork()) == 0) { cout << i << endl; //struct sigaction sigact; sigset_t sigset; int sig; int result = 0; sigemptyset(&sigset); if(i%2 == 0) { if(signal(SIGUSR2, SIG_IGN) == SIG_ERR) { perror("2"); return 2; } sigaddset(&sigset, SIGUSR1); sigprocmask(SIG_BLOCK, &sigset, NULL); } else { if(signal(SIGUSR1, SIG_IGN) == SIG_ERR) { perror("2"); return 2; } sigaddset(&sigset, SIGUSR2); sigprocmask(SIG_BLOCK, &sigset, NULL); } while(true) { int result = sigwait(&sigset, &sig); if(result == 0) { cout << "The caught signal is " << sig << endl; } } exit(0); } else { cout << "Registerd the handler " << pid << endl; handlers[i] = pid; } } //Registering the monitoring process if((pid = fork()) == 0) { sigset_t sigset; int sig; int result = 0; sigemptyset(&sigset); sigaddset(&sigset, SIGUSR1); sigaddset(&sigset, SIGUSR2); sigprocmask(SIG_BLOCK, &sigset, NULL); while(true) { int result = sigwait(&sigset, &sig); if(result == 0) { cout << "The monitored signal is " << sig << endl; } else { cout << "error" << endl; } } } else { reporter = pid; } sleep(3); //Registering the signal generator for(int i=0; i<1; i++) { if((pid = fork()) == 0) { if(signal(SIGUSR1, SIG_IGN) == SIG_ERR) { perror("1"); return 1; } if(signal(SIGUSR2, SIG_IGN) == SIG_ERR) { perror("2"); return 2; } srand(time(0)); while(true) { volatile int signal_id = rand()%2 + 1; cout << "Generating the signal " << signal_id << endl; if(signal_id == 1) { killpg(getpgid(getpid()), SIGUSR1); } else { killpg(getpgid(getpid()), SIGUSR2); } int r = rand()%10 + 1; double s = (double)r/100; sleep(s); } exit(0); } else { cout << "Registered the sender " << pid << endl; senders[i] = pid; } } while(w = wait(&status)) { cout << "Wait on PID " << w << endl; } } void signal_catcher_int(int the_sig) { //cout << "Handling the Ctrl C signal " << endl; for(int i=0; i<1; i++) { kill(senders[i],SIGKILL); } for(int i=0; i<4; i++) { kill(handlers[i],SIGKILL); } kill(reporter,SIGKILL); exit(3); } Any suggestions? Here is a sample of the output as well In the beginning Registerd the handler 9544 Registerd the handler 9545 1 Registerd the handler 9546 Registerd the handler 9547 2 3 0 Registered the sender 9550 Generating the signal 1 The caught signal is 10 The monitored signal is 10 The caught signal is 10 Generating the signal 1 The caught signal is 10 The monitored signal is 10 The caught signal is 10 Generating the signal 1 The caught signal is 10 The monitored signal is 10 The caught signal is 10 Generating the signal 1 The caught signal is 10 The monitored signal is 10 The caught signal is 10 Generating the signal 2 The caught signal is 12 The caught signal is 12 The monitored signal is 12 Generating the signal 2 Generating the signal 2 The caught signal is 12 The caught signal is 12 Generating the signal 1 The caught signal is 12 The monitored signal is 10 The monitored signal is 12 Generating the signal 1 Generating the signal 2 The caught signal is 12 Generating the signal 1 Generating the signal 2 10 The monitored signal is 10 The caught signal is 12 Generating the signal 1 The caught signal is 12 The monitored signal is GenThe caught signal is TheThe caught signal is 10 Generating the signal 2 Later on The monitored signal is GenThe monitored signal is 10 Generating the signal 1 Generating the signal 2 The caught signal is 10 The caught signal is 10 The caught signal is 10 The caught signal is 12 Generating the signal 1 Generating the signal 2 Generating the signal 1 Generating the signal 1 Generating the signal 2 Generating the signal 2 Generating the signal 2 Generating the signal 2 Generating the signal 2 Generating the signal 1 The caught signal is 12 The caught signal is 10 The caught signal is 10 Generating the signal 2 Generating the signal 1 Generating the signal 1 Generating the signal 2 Generating the signal 1 Generating the signal 2 Generating the signal 2 Generating the signal 2 Generating the signal 1 Generating the signal 2 Generating the signal 1 Generating the signal 2 Generating the signal 2 The caught signal is 10 Generating the signal 2 Generating the signal 1 Generating the signal 1 As you can see initially, the signal was generated and handled both by my signal handlers and monitoring processes. But later on the signal was generated a lot, but it was not quite processes in the same magnitude as before. Further I could see very less signal processing by the monitoring process Can anyone please provide some insights. What's going on?

  Read the article

• How to use pthread_atfork() and pthread_once() to reinitialize mutexes in child processes

  - by Blair Zajac

  We have a C++ shared library that uses ZeroC's Ice library for RPC and unless we shut down Ice's runtime, we've observed child processes hanging on random mutexes. The Ice runtime starts threads, has many internal mutexes and keeps open file descriptors to servers. Additionally, we have a few of mutexes of our own to protect our internal state. Our shared library is used by hundreds of internal applications so we don't have control over when the process calls fork(), so we need a way to safely shutdown Ice and lock our mutexes while the process forks. Reading the POSIX standard on pthread_atfork() on handling mutexes and internal state: Alternatively, some libraries might have been able to supply just a child routine that reinitializes the mutexes in the library and all associated states to some known value (for example, what it was when the image was originally executed). This approach is not possible, though, because implementations are allowed to fail *_init() and *_destroy() calls for mutexes and locks if the mutex or lock is still locked. In this case, the child routine is not able to reinitialize the mutexes and locks. On Linux, the this test C program returns EPERM from pthread_mutex_unlock() in the child pthread_atfork() handler. Linux requires adding _NP to the PTHREAD_MUTEX_ERRORCHECK macro for it to compile. This program is linked from this good thread. Given that it's technically not safe or legal to unlock or destroy a mutex in the child, I'm thinking it's better to have pointers to mutexes and then have the child make new pthread_mutex_t on the heap and leave the parent's mutexes alone, thereby having a small memory leak. The only issue is how to reinitialize the state of the library and I'm thinking of reseting a pthread_once_t. Maybe because POSIX has an initializer for pthread_once_t that it can be reset to its initial state. #include <pthread.h> #include <stdlib.h> #include <string.h> static pthread_once_t once_control = PTHREAD_ONCE_INIT; static pthread_mutex_t *mutex_ptr = 0; static void setup_new_mutex() { mutex_ptr = malloc(sizeof(*mutex_ptr)); pthread_mutex_init(mutex_ptr, 0); } static void prepare() { pthread_mutex_lock(mutex_ptr); } static void parent() { pthread_mutex_unlock(mutex_ptr); } static void child() { // Reset the once control. pthread_once_t once = PTHREAD_ONCE_INIT; memcpy(&once_control, &once, sizeof(once_control)); setup_new_mutex(); } static void init() { setup_new_mutex(); pthread_atfork(&prepare, &parent, &child); } int my_library_call(int arg) { pthread_once(&once_control, &init); pthread_mutex_lock(mutex_ptr); // Do something here that requires the lock. int result = 2*arg; pthread_mutex_unlock(mutex_ptr); return result; } In the above sample in the child() I only reset the pthread_once_t by making a copy of a fresh pthread_once_t initialized with PTHREAD_ONCE_INIT. A new pthread_mutex_t is only created when the library function is invoked in the child process. This is hacky but maybe the best way of dealing with this skirting the standards. If the pthread_once_t contains a mutex then the system must have a way of initializing it from its PTHREAD_ONCE_INIT state. If it contains a pointer to a mutex allocated on the heap than it'll be forced to allocate a new one and set the address in the pthread_once_t. I'm hoping it doesn't use the address of the pthread_once_t for anything special which would defeat this. Searching comp.programming.threads group for pthread_atfork() shows a lot of good discussion and how little the POSIX standards really provides to solve this problem. There's also the issue that one should only call async-signal-safe functions from pthread_atfork() handlers, and it appears the most important one is the child handler, where only a memcpy() is done. Does this work? Is there a better way of dealing with the requirements of our shared library?

  Read the article

• HP-UX: libstd_v2 in stack trace of JNI code compiled with g++

  - by Miguel Rentes

  Hello, uname -mr: B.11.23 ia64 g++ --version: g++ (GCC) 4.4.0 java -version: Java(TM) SE Runtime Environment (build 1.6.0.06-jinteg_20_jan_2010_05_50-b00) Java HotSpot(TM) Server VM (build 14.3-b01-jre1.6.0.06-rc1, mixed mode) I'm trying to run a Java application that uses JNI. It is crashing inside the JNI code with the following (abbreviated) stack trace: (0) 0xc0000000249353e0 VMError::report_and_die{_ZN7VMError14report_and_dieEv} + 0x440 at /CLO/Components/JAVA_HOTSPOT/Src/src/share/vm/utilities/vmError.cpp:738 [/opt/java6/jre/lib/IA64W/server/libjvm.so] (1) 0xc000000024559240 os::Hpux::JVM_handle_hpux_signal{_ZN2os4Hpux22JVM_handle_hpux_signalEiP9 __siginfoPvi} + 0x760 at /CLO/Components/JAVA_HOTSPOT/Src/src/os_cpu/hp-ux_ia64/vm/os_hp-ux_ia64.cpp:1051 [/opt/java6/jre/lib/IA64W/server/libjvm.so] (2) 0xc0000000245331c0 os::Hpux::signalHandler{_ZN2os4Hpux13signalHandlerEiP9__siginfoPv} + 0x80 at /CLO/Components/JAVA_HOTSPOT/Src/src/os/hp-ux/vm/os_hp-ux.cpp:4295 [/opt/java6/jre/lib/IA64W/server/libjvm.so] (3) 0xe00000010e002620 ---- Signal 11 (SIGSEGV) delivered ---- (4) 0xc0000000000d2d20 __pthread_mutex_lock + 0x400 at /ux/core/libs/threadslibs/src/common/pthreads/mutex.c:3895 [/usr/lib/hpux64/libpthread.so.1] (5) 0xc000000000342e90 __thread_mutex_lock + 0xb0 at ../../../../../core/libs/libc/shared_em_64/../core/threads/wrappers1.c:273 [/usr/lib/hpux64/libc.so.1] (6) 0xc00000000177dff0 _HPMutexWrapper::lock{_ZN15_HPMutexWrapper4lockEPv} + 0x90 [/usr/lib/hpux64/libstd_v2.so.1] (7) 0xc0000000017e9960 std::basic_string,std::allocator{_ZNSsC1ERKSs} + 0x80 [/usr/lib/hpux64/libstd_v2.so.1] (8) 0xc000000008fd9fe0 JniString::str{_ZNK9JniString3strEv} + 0x50 at eg_handler_jni.cxx:50 [/soft/bus-7_0/lib/libbus_registry_jni.so.7.0.0] (9) 0xc000000008fd7060 pt_efacec_se_aut_frk_cmp_registry_REGHandler::getKey{_ZN44pt_efacec_se_aut_frk_cmp_registry_REGHandler6getKeyEP8_jstringi} + 0xa0 [/soft/bus-7_0/lib/libbus_registry_jni.so.7.0.0] (10) 0xc000000008fd17f0 Java_pt_efacec_se_aut_frk_cmp_registry_REGHandler_getKey__Ljava_lang_String_2I + 0xa0 [/soft/bus-7_0/lib/libbus_registry_jni.so.7.0.0] (11) 0x9fffffffdf400ed0 Internal error (-3) while unwinding stack [/CLO/Components/JAVA_HOTSPOT/Src/src/os_cpu/hp-ux_ia64/vm/thread_hp-ux_ia64.cpp:142] This JNI code and dependencies are being compiled using g++, are multithreaded and 64 bit (-pthread -mlp64 -shared -fPIC). The LD_LIBRARY_PATH environment variable is set the dependencies location, and running ldd on the JNI shared libraries finds them all: ldd libbus_registry_jni.so: libefa-d.so.7 = /soft/bus-7_0/lib/libefa-d.so.7 libbus_registry-d.so.7 = /soft/bus-7_0/lib/libbus_registry-d.so.7 libboost_thread-gcc44-mt-d-1_41.so = /usr/local/lib/libboost_thread-gcc44-mt-d-1_41.so libboost_system-gcc44-mt-d-1_41.so = /usr/local/lib/libboost_system-gcc44-mt-d-1_41.so libboost_regex-gcc44-mt-d-1_41.so = /usr/local/lib/libboost_regex-gcc44-mt-d-1_41.so librt.so.1 = /usr/lib/hpux64/librt.so.1 libstdc++.so.6 = /opt/hp-gcc-4.4.0/lib/gcc/ia64-hp-hpux11.23/4.4.0/../../../hpux64/libstdc++.so.6 libm.so.1 = /usr/lib/hpux64/libm.so.1 libgcc_s.so.0 = /opt/hp-gcc-4.4.0/lib/gcc/ia64-hp-hpux11.23/4.4.0/../../../hpux64/libgcc_s.so.0 libunwind.so.1 = /usr/lib/hpux64/libunwind.so.1 librt.so.1 = /usr/lib/hpux64/librt.so.1 libm.so.1 = /usr/lib/hpux64/libm.so.1 libunwind.so.1 = /usr/lib/hpux64/libunwind.so.1 libdl.so.1 = /usr/lib/hpux64/libdl.so.1 libunwind.so.1 = /usr/lib/hpux64/libunwind.so.1 libc.so.1 = /usr/lib/hpux64/libc.so.1 libuca.so.1 = /usr/lib/hpux64/libuca.so.1 Looking at the stack trace, it seams odd that, although ldd list g++'s libstdc++ is being used, the std:string copy c'tor being reported as used is the one in libstd_v2, the implementation provided by aCC. The crash happens in the following code, when method str() returns: class JniString { std::string m_utf8; public: JniString(JNIEnv* env, jstring instance) { const char* utf8Chars = env-GetStringUTFChars(instance, 0); if (utf8Chars == 0) { env-ExceptionClear(); // RPF throw std::runtime_error("GetStringUTFChars returned 0"); } m_utf8.assign(utf8Chars); env-ReleaseStringUTFChars(instance, utf8Chars); } std::string str() const { return m_utf8; } }; Simultaneous usage of the two C++ implementations could likely be a reason for the crash, but that should not be happening. Any ideas?

  Read the article

• CPU Affinity Masks (Putting Threads on different CPUs)

  - by hahuang65

  I have 4 threads, and I am trying to set thread 1 to run on CPU 1, thread 2 on CPU 2, etc. However, when I run my code below, the affinity masks are returning the correct values, but when I do a sched_getcpu() on the threads, they all return that they are running on CPU 4. Anybody know what my problem here is? Thanks in advance! #define _GNU_SOURCE #include <stdio.h> #include <pthread.h> #include <stdlib.h> #include <sched.h> #include <errno.h> void *pthread_Message(char *message) { printf("%s is running on CPU %d\n", message, sched_getcpu()); } int main() { pthread_t thread1, thread2, thread3, thread4; pthread_t threadArray[4]; cpu_set_t cpu1, cpu2, cpu3, cpu4; char *thread1Msg = "Thread 1"; char *thread2Msg = "Thread 2"; char *thread3Msg = "Thread 3"; char *thread4Msg = "Thread 4"; int thread1Create, thread2Create, thread3Create, thread4Create, i, temp; CPU_ZERO(&cpu1); CPU_SET(1, &cpu1); temp = pthread_setaffinity_np(thread1, sizeof(cpu_set_t), &cpu1); printf("Set returned by pthread_getaffinity_np() contained:\n"); for (i = 0; i < CPU_SETSIZE; i++) if (CPU_ISSET(i, &cpu1)) printf("CPU1: CPU %d\n", i); CPU_ZERO(&cpu2); CPU_SET(2, &cpu2); temp = pthread_setaffinity_np(thread2, sizeof(cpu_set_t), &cpu2); for (i = 0; i < CPU_SETSIZE; i++) if (CPU_ISSET(i, &cpu2)) printf("CPU2: CPU %d\n", i); CPU_ZERO(&cpu3); CPU_SET(3, &cpu3); temp = pthread_setaffinity_np(thread3, sizeof(cpu_set_t), &cpu3); for (i = 0; i < CPU_SETSIZE; i++) if (CPU_ISSET(i, &cpu3)) printf("CPU3: CPU %d\n", i); CPU_ZERO(&cpu4); CPU_SET(4, &cpu4); temp = pthread_setaffinity_np(thread4, sizeof(cpu_set_t), &cpu4); for (i = 0; i < CPU_SETSIZE; i++) if (CPU_ISSET(i, &cpu4)) printf("CPU4: CPU %d\n", i); thread1Create = pthread_create(&thread1, NULL, (void *)pthread_Message, thread1Msg); thread2Create = pthread_create(&thread2, NULL, (void *)pthread_Message, thread2Msg); thread3Create = pthread_create(&thread3, NULL, (void *)pthread_Message, thread3Msg); thread4Create = pthread_create(&thread4, NULL, (void *)pthread_Message, thread4Msg); pthread_join(thread1, NULL); pthread_join(thread2, NULL); pthread_join(thread3, NULL); pthread_join(thread4, NULL); return 0; }

  Read the article

< Previous Page | 2 3 4 5 6 7  | Next Page >