Search Results

Search found 3548 results on 142 pages for 'unix'.

Page 55/142 | < Previous Page | 51 52 53 54 55 56 57 58 59 60 61 62  | Next Page >

  • Why is the value of this string, in a bash script, being executing?

    - by Ross
    Hello Why is this script executing the string in the if statement: #!/bin/bash FILES="*" STRING='' for f in $FILES do if ["$STRING" = ""] then echo first STRING='hello' else STRING="$STRING hello" fi done echo $STRING when run it with sh script.sh outputs: first lesscd.sh: line 7: [hello: command not found lesscd.sh: line 7: [hello hello: command not found lesscd.sh: line 7: [hello hello hello: command not found lesscd.sh: line 7: [hello hello hello hello: command not found lesscd.sh: line 7: [hello hello hello hello hello: command not found hello hello hello hello hello hello p.s. first attempt at a shell script thanks

    Read the article

  • using bash: write bit representation of integer to file

    - by theseion
    Hullo First, I want to use bash for this and the script should run on as many systems as possible (I don't know if the target system will have python or whatever installed). Here's the problem: I have a file with binary data and I need to replace a few bytes in a certain position. I've come up with the following to direct bash to the offset and show me that it found the place I want: dd bs=1 if=file iseek=24 conv=block cbs=2 | hexdump Now, to use "file" as the output: echo anInteger | dd bs=1 of=hextest.txt oseek=24 conv=block cbs=2 This seems to work just fine, I can review the changes made in a hex editor. Problem is, "anInteger" will be written as the ASCII representation of that integer (which makes sense) but I need to write the binary representation. How do I tell the command to convert the input to binary (possibly from a hex)?

    Read the article

  • Safely get rid of "You have new mail in /var/mail" on a Mac?

    - by viatropos
    I was messing around with sendmail in Rails a year ago and have had this message popping up in the terminal after every command ever since: You have new mail in /var/mail/Lance How do I properly get rid of that so the message goes away? I ever use any of that functionality and don't have mail on my computer. There's one file in /var/mail called lance, and it's huge. Can I just remove it?

    Read the article

  • Hudson trigget builds remotely gives a forbidden 403 error

    - by Ritesh M Nayak
    I have a shell script on the same machine that hudson is deployed on and upon executing it, it calls wget on a hudson build trigger URL. Since its the same machine, I access it as http://localhost:8080/hudson/job/jobname/build?token=sometoken Typically, this is supposed to trigger a build on the project. But I get a 403 forbidden when I do this. Anybody has any idea why? I have tried this using a browser and it triggers the build, but via the command line it doesn't seem to work. Any ideas?

    Read the article

  • Proper pidfile usage

    - by Moev4
    I am unclear on the need and the usage of a pid-file and I wanted to know what is the correct usage of a pidfile and what are the best practices surrounding it.

    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

  • Bash: using commands as parameters (specificly cd, dirname and find)

    - by sixtyfootersdude
    This command and output: % find . -name file.xml 2> /dev/null ./a/d/file.xml % So this command and output: % dirname `find . -name file.xml 2> /dev/null` ./a/d % So you would expect that this command: % cd `dirname `find . -name file.xml 2> /dev/null`` Would change the current directory to ./a/d. Strangely this does not work. When I type cd ./a/d. The directory change works. However I cannot find out why the above does not work...

    Read the article

  • Why does the rename() syscall prohibit moving a directory that I can't write to a different director

    - by Daniel Papasian
    I am trying to understand why this design decision was made with the rename() syscall in 4.2BSD. There's nothing I'm trying to solve here, just understand the rationale for the behavior itself. 4.2BSD saw the introduction of the rename() syscall for the purpose of allowing atomic renames/moves of files. From 4.3BSD-Reno/src/sys/ufs/ufs_vnops.c: /* * If ".." must be changed (ie the directory gets a new * parent) then the source directory must not be in the * directory heirarchy above the target, as this would * orphan everything below the source directory. Also * the user must have write permission in the source so * as to be able to change "..". We must repeat the call * to namei, as the parent directory is unlocked by the * call to checkpath(). */ if (oldparent != dp->i_number) newparent = dp->i_number; if (doingdirectory && newparent) { VOP_LOCK(fndp->ni_vp); error = ufs_access(fndp->ni_vp, VWRITE, tndp->ni_cred); VOP_UNLOCK(fndp->ni_vp); So clearly this check was added intentionally. My question is - why? Is this behavior supposed to be intuitive? The effect of this is that one cannot move a directory (located in a directory that one can write) that one cannot write to another directory that one can write to atomically. You can, however, create a new directory, move the links over (assuming one has read access to the directory), and then remove one's write bit on the directory. You just can't do so atomically. % cd /tmp % mkdir stackoverflow-question % cd stackoverflow-question % mkdir directory-1 % mkdir directory-2 % mkdir directory-1/directory-i-cant-write % echo "foo" > directory-1/directory-i-cant-write/contents % chmod 000 directory-1/directory-i-cant-write/contents % chmod 000 directory-1/directory-i-cant-write % mv directory-1/directory-i-cant-write directory-2 mv: rename directory-1/directory-i-cant-write to directory-2/directory-i-cant-write: Permission denied We now have a directory I can't write with contents I can't read that I can't move atomically. I can, however, achieve the same effect non-atomically by changing permissions, making the new directory, using ln to create the new links, and changing permissions. (Left as an exercise to the reader) . and .. are special cased already, so I don't particularly buy that it is intuitive that if I can't write a directory I can't "change .." which is what the source suggests. Is there any reason for this besides it being the perceived correct behavior by the author of the code? Is there anything bad that can happen if we let people atomically move directories (that they can't write) between directories that they can write?

    Read the article

  • late binding in C

    - by benjamin button
    How can late binding can be achieved in c language? can anybody please provide an example. i think it can be achieved using dlopen and dlsym but i am not sure about it.please correct me if i am wrong!

    Read the article

  • SIMPLE BASH Programming.

    - by atif089
    I am a newbie to BASH so please dont mind my stupid questions because I am not able to get any good sources to learn that. I want to create a script to display filename and its size. This is what the code is like filename=$1 if [ -f $filename ]; then filesize=`du -b $1` echo "The name of file is $1" echo "Its size is $filesize" else echo "The file specified doesnot exists" fi The output is like this $ ./filesize.sh aa The name of file is aa Its size is 88 aa But in the last line I dont want to show the name of the file. How do I do that ? I want to do the same thing using wc as well.

    Read the article

  • Custom installation directories

    - by Alex Farber
    Let's say I am writing installation script for the program which contains executable file and shared library. By default, this script places executable to /usr/local/bin, and shared library to /usr/local/lib. In this case my program may be executed by any user by typing its name in the command line. Suppose that user selects custom installation directory, like ~/myprogram/. Is it user's responsibility to ensure that my program may be executed, or my installation script must do this?

    Read the article

  • Build Systems for PHP Web Apps

    - by macinjosh
    I want to start automating more of my web development process so I'm looking for a build system. I write mostly PHP apps on Mac OS X and deploy Linux servers over FTP. A lot of my clients have basic hosting providers so shell access to their servers is typically not available, however remote MySQL access is usually present. Here is what I want to do with a build system: When Building: Lint JavaScript Files Validate CSS Files Validate HTML Files Minify and concatenate JS and CSS files Verify PHP Syntax Set Debug/Production flags When Deploying Checkout latest version from SVN Run build process Upload files to server via FTP Run SQL scripts on remote DB I realize this is a lot of work to automate but I think it would be worth it. So what is the best way to start down this path? Is there a system that can handle builds and deploys, or should I search for separate solutions? What systems would you recommend?

    Read the article

  • Shell script to process files

    - by Harish
    I need to write a Shell Script to process a huge folder of nearly 20 levels.I have to process each and every file and check which files contain lines like select insert update When I mean line it should take the line till I find a semicolon in that file. I should get a result like this C:/test.java select * from dual C:/test.java select * from test C:/test1.java select * from tester C:/test1.java select * from dual and so on.Right now I have a script to read all the files #!bin/ksh FILE=<FILEPATH to be traversed> TEMPFILE=<Location of Temp file> cd $FILE for f in `find . ! -type d`; do cat $FILE/addedText.txt>>$TEMPFILE/newFile.txt cat $f>>$TEMPFILE/newFile.txt rm $f cat $TEMPFILE/newFile.txt>>$f rm $TEMPFILE/newFile.txt done I have very little knowledge of awk and sed to proceed further in reading each file and achieve what I want to.Can anyone help me in this

    Read the article

  • Regex for capturing number in brackets

    - by neversaint
    I have a lines like this NF419andZNF773 (e=10^-92,). ZNF571 (e=2 10^-14,) What's the regex for extracting the results above so that it gives NF419andZNF773 - 10^-92 ZNF571 - 2 10^-14 I tried this but fail. $line =~ /(\w+)\s\(e=\s(.*),\)/; print "$1 - $2\n";

    Read the article

  • iteratively creating graphs

    - by Andrei
    I have a bunch of files containing x and y coordinates, representing time and value (space-separated, but can be amended) For example: 15:06:59 0.0140 ....... I want to create a word file (or some equivalent) to show all these graphs. Right now I am using Excel. It pretty daunting task, as I ahve to plug paste numbers in two rows for each graph, and I have many of them. Thanks

    Read the article

  • Can I use POSIX signals in my Perl program to create event-driven programming?

    - by Shiftbit
    Is there any POSIX signals that I could utilize in my Perl program to create event-driven programming? Currently, I have multi-process program that is able to cross communicate but my parent thread is only able to listen to listen at one child at a time. foreach (@proc) { sysread(${$_}{'read'}, my $line, 100); #problem here chomp($line); print "Parent hears: $line\n"; } The problem is that the parent sits in a continual wait state until it receives it a signal from the first child before it can continue on. I am relying on 'pipe' for my intercommunication. My current solution is very similar to: http://stackoverflow.com/questions/2558098/how-can-i-use-pipe-to-facilitate-interprocess-communication-in-perl If possible I would like to rely on a $SIG{...} event or any non-CPAN solution. Update: As Jonathan Leffler mentioned, kill can be used to send a signal: kill USR1 = $$; # send myself a SIGUSR1 My solution will be to send a USR1 signal to my child process. This event tells the parent to listen to the particular child. child: kill USR1 => $parentPID if($customEvent); syswrite($parentPipe, $msg, $buffer); #select $parentPipe; print $parentPipe $msg; parent: $SIG{USR1} = { #get child pid? sysread($array[$pid]{'childPipe'}, $msg, $buffer); }; But how do I get my the source/child pid that signaled the parent? Have the child Identify itself in its message. What happens if two children signal USR1 at the same time?

    Read the article

  • Viewing an EXE File

    - by Steve
    I was attempting to install an exe that requires a serial number before the install, which the vendor has not provided to us yet. This got my wheels turning about whether there is any information that can be gained from viewing an exe using a hex editor/VI/etc? Using VI to view an exe, I can see some sections of plain text, but it is difficult to determine what it refers to without any context around it. Is it possible to determine any information by reading an exe? Thanks

    Read the article

  • Logging from multiple apps/processes to a single log file

    - by Andrew
    Our app servers (weblogic) all use log4j to log to the same file on a network share. On top of this we have all web apps in a managed server logging errors to a common error.log. I can't imagine this is a good idea but wanted to hear from some pros. I know that each web app has its own classloader, so any thread synchronization only occurs within the app. So what happens when multiple processes start converging on a single log file? Can we expect interspersed log statements? Performance problems? What about multiple web apps logging to a common log file? The environment is Solaris.

    Read the article

< Previous Page | 51 52 53 54 55 56 57 58 59 60 61 62  | Next Page >