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  • How to lock non-browser clients from submitting a request?

    - by Thomas Kohl
    I want to block non-browser clients from accessing certain pages / successfully making a request. The website content is served to authenticated users. What happens is that our user gives his credentials to our website to 3rd party - it can be another website or a mobile application - that performs requests on his behalf. Say there is a form that the user fills out and sends a message. Can I protect this form so that the server processing the submission can tell whether the user has submitted it directly from the browser or not? I don't want to use CAPTCHA for usability reasons. Can I do it with some javascript?

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  • MySQL locking problem

    - by teehoo
    I have a simple setup of a set of writers and a set of readers working with a MySQL ISAM table. The writers are only inserting rows while the readers are only checking for new rows. OK, so I know that I don't need a lock in this situation, since I'm not modifying existing rows. However my Writers are accessing one more table that does need a lock. I piece of information seems irrelevant except for the following limitation stated in the MySQL documentation: A session that requires locks must acquire all the locks that it needs in a single LOCK TABLES statement. While the locks thus obtained are held, the session can access only the locked tables. For example, in the following sequence of statements, an error occurs for the attempt to access t2 because it was not locked in the LOCK TABLES statement: So to access the table I want to insert rows into, I NEED to lock it, which is causing me performance problems. Any suggestions of how to get around this?

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  • How to lock the Screen customly? Just like WaveSecure in Android

    - by HackNone
    I want to do a demo just like WaveSecure, which win Android Develop Challenge 2 with a third place. Now I have a problem in locking the screen customly, so I want to know how WaveSecure achieve its locking function, as the following picture show: http://goo.gl/XlPP When the mobile is locked, WaveSecure can require customer to input their own password. So I think WaveSecure must replace Android's original locking function. And I also google it, but I didn't find anything helpful. I only find two packages may be helpful. They are: android.app.KeyguardManager android.os.PowerManager But after I reading the Android Docs, I still can't have an idea on it. Can you help me? Thx:)

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  • Outlook 2010 - HTML Images not downloaded - at all - by default

    - by Scott Lock
    Maybe it's just me but I found this "Security Feature" of Office 2010 a bit annyoing out of the box.  Outlook does not download any pictures by default for HTML emails.  Now this is nothing new, but what is different is that Outlook 2010 has added another layer of security around the pictures.  You now have the option to finely tune when things are downloaded.  The side affect is that nothing is downloaded at all.  And when I would click on "Download Images" on an email, it still would not show the images.  I found that I had to explicitly tell Outlook to download HTML images and then restart Windows.  It did not work if I simply restarted Office.  Again, maybe this was just me.  Here's what you need to do in Outlook 2010 to enable images for HTML: Click on the new "File" tab Click on "Options" Click on "Trust Center" Clicn on "Trust Center Settings" Uncheck the "Don't download pictures automatically in HTML e-mail messages or RSS items" check box Click the "Okay" button Exit Outlook 2010 Again, for me I had to restart Windows (Windows 7 64bit, Office 2010 64bit) to get this to "take affect".

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  • How do you lock down & secure files stored on server in ASP.NET?

    - by Jon
    How do I go about securing files that are stored on the server? We have an ASP.NET app which generates PDFs. These are not stored in the wwwroot folder but in another folder i.e. C:\inetpub\data. This provides more security but maybe not enough. The ASP.NET/IIS process will need write access to this folder so it generate the PDFs there. Once the pdf is generated, it can be viewed using an ASP.NET form called viewpdf.aspx with the file to be viewed add to the query string like so viewpdf.aspx?FILE=mynewfile.pdf. This is loaded from a gridview. The full path to C:\inetpub\data is resolved and loaded in the Page_load event of the viewer page. Now I'm wondering how to secure this. Anybody could just view the file. Not by entering in the URL, as it won't been seen by IIS (its not in wwwroot), but could change the querystring in the viewpdf page. How do I stop anybody hacking this?

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  • SQL Compact Edition 3.5 SP 1 - LockTimeOutException - how to debug?

    - by Bob King
    Intermittently in our app, we encounter LockTimeoutExceptions being throw from SQL CE. We've recently upgraded to 3.5 SP 1, and a number of them seem to have gone away, but we still do see them occasionally. I'm certain it's a bug in our code (which is multi-threaded) but I haven't been able to pin it down precisely. Does anyone have any good techniques for debugging this problem? The exceptions log like this (there's never a stack trace for these exceptions): SQL Server Compact timed out waiting for a lock. The default lock time is 2000ms for devices and 5000ms for desktops. The default lock timeout can be increased in the connection string using the ssce: default lock timeout property. [ Session id = 6,Thread id = 7856,Process id = 10116,Table name = Product,Conflict type = s lock (x blocks),Resource = DDL ] Our database is read-heavy, but does seldom writes, and I think I've got everything protected where it needs to be. EDIT: SQL CE already automatically uses NOLOCK http://msdn.microsoft.com/en-us/library/ms172398(sql.90).aspx

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  • Do Managers in Python Multiprocessing module lock the shared data?

    - by AnonProcess
    This Question has been asked before: http://stackoverflow.com/questions/2936626/how-to-share-a-dictionary-between-multiple-processes-in-python-without-locking However I have several doubts regarding the program given in the answer: The issue is that the following step isn't atomic d['blah'] += 1 Even with locking the answer provided in that question would lead to random results. Since Process 1 read value of d['blah'] saves it on the stack increments it and again writes it. In Between a Process 2 can read the d['blah'] as well. Locking means that while d['blah'] is being written or read no other process can access it. Can someone clarify my doubts?

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  • (Windows) How to lock all applications (explorer, task manager etc.) and make only the browser activ

    - by Unni
    I'm trying to run only the browser in the system - locking access to everything else. Only the supervisor can resume the normal functioning of the system after giving a password. This kind of activity is usually done by virus. Disabling the registry for Task manager etc. Does anyone know of any source available that does this? I might be able to pull it off in Windows XP. But have anyone tried this in Windows 7 ? The aim is to to emulate the Chrome OS on Windows. Only the browser. Nothing else.

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  • How to get a green to show up like the charging battery on the iPhone lock screen?

    - by tarheel
    I am trying to get a color to show up on screen just like the charging battery (shown here): After looking at the Apple Documentation on UIColor here, I have attempted using both colorWithHue:saturation:brightness:aplha: and colorWithRed:green:blue:alpha: to get a color to show up like that. For example when I use colorWithHue:.3 saturation:.84 brightness:1 alpha:.5 on a black background, it renders a color like this: or the colorWithRed:0 green:1 blue:0 alpha:.5 on a black background shows up like this: It doesn't have that translucent or glossy look to it. Is there a better method to use? Or do I just not have the values right? (I have tried many combinations)

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  • .net- open excel file, format the file and save

    - by Lock
    I have an ASP web service that uses the Crystal Reports API to download an Excel report. Now, there is a few things I do not like about the Excel report that Crystal generates: - The column widths are static (as in they are not adjusted for the content). - I can't format the header row to be bold - If I suppress a data column in the report, it comes out in the Excel spreadsheet as a blank column. I currently use PHP to open the excel file, autosize the columns, bold the heading and remove blank columns, although using the PHPExcel class for this doesn't work well when the spreadsheet is only a few 100kb in size. I am thinking if I move this activity into the .NET web service, the performance will be much better. Does anyone know an efficient way of opening a Excel file and performing the operations listed above?

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  • SEO for duplicate sites with multiple domain extensions

    - by lock
    I am running business in different nations and I got domains for example www.mydomain.com www.mydomain.us www.mydomain.ca www.mydomain.uk www.mydomain.com.au So, if I run same website with same content (of course there will be little changes like address, etc.) as all these domains has same content will it be considered as spam or will the domains rank well as per the country? Also, is there solutions if Google considers this as spam.

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  • Subtle C++ mistake, can you spot it?

    - by aaa
    I ran into a subtle C++ gotcha, took me while to resolve it. Can you spot it? class synchronized_container { boost::mutex mutex_; std::vector <T> container_; void push_back(const T &value) { boost::scoped_lock(mutex_); // raii mutex lock container_.push_back(value); } ... }; scoped lock is a raii mutex lock, obtains lock on constructor, release lock in destructor. The program will work as expected in serial, but will may occasionally produce weird stuff with more than one thread.

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  • Why is there a /etc/init.d/mysql file on this Slackware machine? How could it have gotten there?

    - by jasonspiro
    A client of my IT-consulting service owns a web-development shop. He's been having problems with a Slackware 12.0 server running MySQL 5.0.67. The machine was set up by the client's sysadmin, who left on bad terms. My client no longer employs a sysadmin. As far as I can tell, the only copy of MySQL that's installed is the one described in /var/log/packages/mysql-5.0.67-i486-1: PACKAGE NAME: mysql-5.0.67-i486-1 COMPRESSED PACKAGE SIZE: 16828 K UNCOMPRESSED PACKAGE SIZE: 33840 K PACKAGE LOCATION: /var/slapt-get/archives/./slackware/ap/mysql-5.0.67-i486-1.tgz PACKAGE DESCRIPTION: mysql: mysql (SQL-based relational database server) mysql: mysql: MySQL is a fast, multi-threaded, multi-user, and robust SQL mysql: (Structured Query Language) database server. It comes with a nice API mysql: which makes it easy to integrate into other applications. mysql: mysql: The home page for MySQL is http://www.mysql.com/ mysql: mysql: mysql: mysql: FILE LIST: ./ var/ var/lib/ var/lib/mysql/ var/run/ var/run/mysql/ install/ install/doinst.sh install/slack-desc usr/ usr/include/ usr/include/mysql/ usr/include/mysql/my_alloc.h usr/include/mysql/sql_common.h usr/include/mysql/my_dbug.h usr/include/mysql/errmsg.h usr/include/mysql/my_pthread.h usr/include/mysql/my_list.h usr/include/mysql/mysql.h usr/include/mysql/sslopt-vars.h usr/include/mysql/my_config.h usr/include/mysql/mysql_com.h usr/include/mysql/m_string.h usr/include/mysql/sslopt-case.h usr/include/mysql/my_xml.h usr/include/mysql/sql_state.h usr/include/mysql/my_global.h usr/include/mysql/my_sys.h usr/include/mysql/mysqld_ername.h usr/include/mysql/mysqld_error.h usr/include/mysql/sslopt-longopts.h usr/include/mysql/keycache.h usr/include/mysql/my_net.h usr/include/mysql/mysql_version.h usr/include/mysql/my_no_pthread.h usr/include/mysql/decimal.h usr/include/mysql/readline.h usr/include/mysql/my_attribute.h usr/include/mysql/typelib.h usr/include/mysql/my_dir.h usr/include/mysql/raid.h usr/include/mysql/m_ctype.h usr/include/mysql/mysql_embed.h usr/include/mysql/mysql_time.h usr/include/mysql/my_getopt.h usr/lib/ usr/lib/mysql/ usr/lib/mysql/libmysqlclient_r.so.15.0.0 usr/lib/mysql/libmysqlclient_r.la usr/lib/mysql/libmyisammrg.a usr/lib/mysql/libmystrings.a usr/lib/mysql/libmyisam.a usr/lib/mysql/libmysqlclient.so.15.0.0 usr/lib/mysql/libmysqlclient_r.a usr/lib/mysql/libmysqlclient.a usr/lib/mysql/libheap.a usr/lib/mysql/libvio.a usr/lib/mysql/libmysqlclient.la usr/lib/mysql/libmysys.a usr/lib/mysql/libdbug.a usr/bin/ usr/bin/comp_err usr/bin/my_print_defaults usr/bin/resolve_stack_dump usr/bin/msql2mysql usr/bin/mysqltestmanager-pwgen usr/bin/myisampack usr/bin/replace usr/bin/mysqld_multi usr/bin/mysqlaccess usr/bin/mysql_install_db usr/bin/innochecksum usr/bin/myisam_ftdump usr/bin/mysqlcheck usr/bin/mysqltest usr/bin/mysql_upgrade_shell usr/bin/mysql_secure_installation usr/bin/mysql_fix_extensions usr/bin/mysqld_safe usr/bin/mysql_explain_log usr/bin/mysqlimport usr/bin/myisamlog usr/bin/mysql_tzinfo_to_sql usr/bin/mysql_upgrade usr/bin/mysqltestmanager usr/bin/mysql_fix_privilege_tables usr/bin/mysql_find_rows usr/bin/mysql_convert_table_format usr/bin/mysqltestmanagerc usr/bin/mysqlhotcopy usr/bin/mysqldump usr/bin/mysqlshow usr/bin/mysqlbug usr/bin/mysql_config usr/bin/mysqldumpslow usr/bin/mysql_waitpid usr/bin/mysqlbinlog usr/bin/mysql_client_test usr/bin/perror usr/bin/mysql usr/bin/myisamchk usr/bin/mysql_setpermission usr/bin/mysqladmin usr/bin/mysql_zap usr/bin/mysql_tableinfo usr/bin/resolveip usr/share/ usr/share/mysql/ usr/share/mysql/errmsg.txt usr/share/mysql/swedish/ usr/share/mysql/swedish/errmsg.sys usr/share/mysql/mysql_system_tables_data.sql usr/share/mysql/mysql.server usr/share/mysql/hungarian/ usr/share/mysql/hungarian/errmsg.sys usr/share/mysql/norwegian/ usr/share/mysql/norwegian/errmsg.sys usr/share/mysql/slovak/ usr/share/mysql/slovak/errmsg.sys usr/share/mysql/spanish/ usr/share/mysql/spanish/errmsg.sys usr/share/mysql/polish/ usr/share/mysql/polish/errmsg.sys usr/share/mysql/ukrainian/ usr/share/mysql/ukrainian/errmsg.sys usr/share/mysql/danish/ usr/share/mysql/danish/errmsg.sys usr/share/mysql/romanian/ usr/share/mysql/romanian/errmsg.sys usr/share/mysql/english/ usr/share/mysql/english/errmsg.sys usr/share/mysql/charsets/ usr/share/mysql/charsets/latin2.xml usr/share/mysql/charsets/greek.xml usr/share/mysql/charsets/koi8r.xml usr/share/mysql/charsets/latin1.xml usr/share/mysql/charsets/cp866.xml usr/share/mysql/charsets/geostd8.xml usr/share/mysql/charsets/cp1250.xml usr/share/mysql/charsets/koi8u.xml usr/share/mysql/charsets/cp852.xml usr/share/mysql/charsets/hebrew.xml usr/share/mysql/charsets/latin7.xml usr/share/mysql/charsets/README usr/share/mysql/charsets/ascii.xml usr/share/mysql/charsets/cp1251.xml usr/share/mysql/charsets/macce.xml usr/share/mysql/charsets/latin5.xml usr/share/mysql/charsets/Index.xml usr/share/mysql/charsets/macroman.xml usr/share/mysql/charsets/cp1256.xml usr/share/mysql/charsets/keybcs2.xml usr/share/mysql/charsets/swe7.xml usr/share/mysql/charsets/armscii8.xml usr/share/mysql/charsets/dec8.xml usr/share/mysql/charsets/cp1257.xml usr/share/mysql/charsets/hp8.xml usr/share/mysql/charsets/cp850.xml usr/share/mysql/korean/ usr/share/mysql/korean/errmsg.sys usr/share/mysql/german/ usr/share/mysql/german/errmsg.sys usr/share/mysql/mi_test_all.res usr/share/mysql/greek/ usr/share/mysql/greek/errmsg.sys usr/share/mysql/french/ usr/share/mysql/french/errmsg.sys usr/share/mysql/mysql_fix_privilege_tables.sql usr/share/mysql/dutch/ usr/share/mysql/dutch/errmsg.sys usr/share/mysql/serbian/ usr/share/mysql/serbian/errmsg.sys usr/share/mysql/mysql_system_tables.sql usr/share/mysql/my-huge.cnf usr/share/mysql/portuguese/ usr/share/mysql/portuguese/errmsg.sys usr/share/mysql/japanese/ usr/share/mysql/japanese/errmsg.sys usr/share/mysql/mysql_test_data_timezone.sql usr/share/mysql/russian/ usr/share/mysql/russian/errmsg.sys usr/share/mysql/czech/ usr/share/mysql/czech/errmsg.sys usr/share/mysql/fill_help_tables.sql usr/share/mysql/estonian/ usr/share/mysql/estonian/errmsg.sys usr/share/mysql/my-medium.cnf usr/share/mysql/norwegian-ny/ usr/share/mysql/norwegian-ny/errmsg.sys usr/share/mysql/my-small.cnf usr/share/mysql/mysql-log-rotate usr/share/mysql/italian/ usr/share/mysql/italian/errmsg.sys usr/share/mysql/my-large.cnf usr/share/mysql/ndb-config-2-node.ini usr/share/mysql/binary-configure usr/share/mysql/mi_test_all usr/share/mysql/mysqld_multi.server usr/share/mysql/my-innodb-heavy-4G.cnf usr/doc/ usr/doc/mysql-5.0.67/ usr/doc/mysql-5.0.67/README usr/doc/mysql-5.0.67/Docs/ usr/doc/mysql-5.0.67/Docs/INSTALL-BINARY usr/doc/mysql-5.0.67/COPYING usr/info/ usr/info/mysql.info.gz usr/libexec/ usr/libexec/mysqld usr/libexec/mysqlmanager usr/man/ usr/man/man8/ usr/man/man8/mysqlmanager.8.gz usr/man/man8/mysqld.8.gz usr/man/man1/ usr/man/man1/mysql_zap.1.gz usr/man/man1/mysql_setpermission.1.gz usr/man/man1/mysql_tzinfo_to_sql.1.gz usr/man/man1/msql2mysql.1.gz usr/man/man1/mysql_tableinfo.1.gz usr/man/man1/mysql_explain_log.1.gz usr/man/man1/mysqlcheck.1.gz usr/man/man1/comp_err.1.gz usr/man/man1/my_print_defaults.1.gz usr/man/man1/mysqlbinlog.1.gz usr/man/man1/myisam_ftdump.1.gz usr/man/man1/mysql_upgrade.1.gz usr/man/man1/mysql.1.gz usr/man/man1/mysql_client_test.1.gz usr/man/man1/resolve_stack_dump.1.gz usr/man/man1/mysql_fix_extensions.1.gz usr/man/man1/mysqlmanagerc.1.gz usr/man/man1/mysql_config.1.gz usr/man/man1/mysqlshow.1.gz usr/man/man1/myisamlog.1.gz usr/man/man1/replace.1.gz usr/man/man1/mysqlmanager-pwgen.1.gz usr/man/man1/mysqltest.1.gz usr/man/man1/innochecksum.1.gz usr/man/man1/mysqladmin.1.gz usr/man/man1/perror.1.gz usr/man/man1/mysql_waitpid.1.gz usr/man/man1/mysql_convert_table_format.1.gz usr/man/man1/mysqlman.1.gz usr/man/man1/mysqlimport.1.gz usr/man/man1/mysqlbug.1.gz usr/man/man1/mysql_find_rows.1.gz usr/man/man1/myisampack.1.gz usr/man/man1/myisamchk.1.gz usr/man/man1/mysql_fix_privilege_tables.1.gz usr/man/man1/mysql-stress-test.pl.1.gz usr/man/man1/resolveip.1.gz usr/man/man1/make_win_bin_dist.1.gz usr/man/man1/mysqlhotcopy.1.gz usr/man/man1/mysqld_multi.1.gz usr/man/man1/safe_mysqld.1.gz usr/man/man1/mysql_secure_installation.1.gz usr/man/man1/mysql_install_db.1.gz usr/man/man1/mysqldump.1.gz usr/man/man1/mysql-test-run.pl.1.gz usr/man/man1/mysqld_safe.1.gz usr/man/man1/mysqlaccess.1.gz usr/man/man1/mysql.server.1.gz usr/man/man1/make_win_src_distribution.1.gz etc/ etc/rc.d/ etc/rc.d/rc.mysqld.new etc/my-huge.cnf etc/my-medium.cnf etc/my-small.cnf etc/my-large.cnf /etc/rc.d/rc.mysqld is an ordinary Slackware-type start/stop script: #!/bin/sh # Start/stop/restart mysqld. # # Copyright 2003 Patrick J. Volkerding, Concord, CA # Copyright 2003 Slackware Linux, Inc., Concord, CA # # This program comes with NO WARRANTY, to the extent permitted by law. # You may redistribute copies of this program under the terms of the # GNU General Public License. # To start MySQL automatically at boot, be sure this script is executable: # chmod 755 /etc/rc.d/rc.mysqld # Before you can run MySQL, you must have a database. To install an initial # database, do this as root: # # su - mysql # mysql_install_db # # Note that step one is becoming the mysql user. It's important to do this # before making any changes to the database, or mysqld won't be able to write # to it later (this can be fixed with 'chown -R mysql.mysql /var/lib/mysql'). # To allow outside connections to the database comment out the next line. # If you don't need incoming network connections, then leave the line # uncommented to improve system security. #SKIP="--skip-networking" # Start mysqld: mysqld_start() { if [ -x /usr/bin/mysqld_safe ]; then # If there is an old PID file (no mysqld running), clean it up: if [ -r /var/run/mysql/mysql.pid ]; then if ! ps axc | grep mysqld 1> /dev/null 2> /dev/null ; then echo "Cleaning up old /var/run/mysql/mysql.pid." rm -f /var/run/mysql/mysql.pid fi fi /usr/bin/mysqld_safe --datadir=/var/lib/mysql --pid-file=/var/run/mysql/mysql.pid $SKIP & fi } # Stop mysqld: mysqld_stop() { # If there is no PID file, ignore this request... if [ -r /var/run/mysql/mysql.pid ]; then killall mysqld # Wait at least one minute for it to exit, as we don't know how big the DB is... for second in 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 \ 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 60 ; do if [ ! -r /var/run/mysql/mysql.pid ]; then break; fi sleep 1 done if [ "$second" = "60" ]; then echo "WARNING: Gave up waiting for mysqld to exit!" sleep 15 fi fi } # Restart mysqld: mysqld_restart() { mysqld_stop mysqld_start } case "$1" in 'start') mysqld_start ;; 'stop') mysqld_stop ;; 'restart') mysqld_restart ;; *) echo "usage $0 start|stop|restart" esac But there's also an unexpected init script on the machine, named /etc/init.d/mysql: #!/bin/sh # Copyright Abandoned 1996 TCX DataKonsult AB & Monty Program KB & Detron HB # This file is public domain and comes with NO WARRANTY of any kind # MySQL daemon start/stop script. # Usually this is put in /etc/init.d (at least on machines SYSV R4 based # systems) and linked to /etc/rc3.d/S99mysql and /etc/rc0.d/K01mysql. # When this is done the mysql server will be started when the machine is # started and shut down when the systems goes down. # Comments to support chkconfig on RedHat Linux # chkconfig: 2345 64 36 # description: A very fast and reliable SQL database engine. # Comments to support LSB init script conventions ### BEGIN INIT INFO # Provides: mysql # Required-Start: $local_fs $network $remote_fs # Should-Start: ypbind nscd ldap ntpd xntpd # Required-Stop: $local_fs $network $remote_fs # Default-Start: 2 3 4 5 # Default-Stop: 0 1 6 # Short-Description: start and stop MySQL # Description: MySQL is a very fast and reliable SQL database engine. ### END INIT INFO # If you install MySQL on some other places than /usr, then you # have to do one of the following things for this script to work: # # - Run this script from within the MySQL installation directory # - Create a /etc/my.cnf file with the following information: # [mysqld] # basedir=<path-to-mysql-installation-directory> # - Add the above to any other configuration file (for example ~/.my.ini) # and copy my_print_defaults to /usr/bin # - Add the path to the mysql-installation-directory to the basedir variable # below. # # If you want to affect other MySQL variables, you should make your changes # in the /etc/my.cnf, ~/.my.cnf or other MySQL configuration files. # If you change base dir, you must also change datadir. These may get # overwritten by settings in the MySQL configuration files. #basedir= #datadir= # Default value, in seconds, afterwhich the script should timeout waiting # for server start. # Value here is overriden by value in my.cnf. # 0 means don't wait at all # Negative numbers mean to wait indefinitely service_startup_timeout=900 # The following variables are only set for letting mysql.server find things. # Set some defaults pid_file=/var/run/mysql/mysql.pid server_pid_file=/var/run/mysql/mysql.pid use_mysqld_safe=1 user=mysql if test -z "$basedir" then basedir=/usr bindir=/usr/bin if test -z "$datadir" then datadir=/var/lib/mysql fi sbindir=/usr/sbin libexecdir=/usr/libexec else bindir="$basedir/bin" if test -z "$datadir" then datadir="$basedir/data" fi sbindir="$basedir/sbin" libexecdir="$basedir/libexec" fi # datadir_set is used to determine if datadir was set (and so should be # *not* set inside of the --basedir= handler.) datadir_set= # # Use LSB init script functions for printing messages, if possible # lsb_functions="/lib/lsb/init-functions" if test -f $lsb_functions ; then . $lsb_functions else log_success_msg() { echo " SUCCESS! $@" } log_failure_msg() { echo " ERROR! $@" } fi PATH=/sbin:/usr/sbin:/bin:/usr/bin:$basedir/bin export PATH mode=$1 # start or stop shift other_args="$*" # uncommon, but needed when called from an RPM upgrade action # Expected: "--skip-networking --skip-grant-tables" # They are not checked here, intentionally, as it is the resposibility # of the "spec" file author to give correct arguments only. case `echo "testing\c"`,`echo -n testing` in *c*,-n*) echo_n= echo_c= ;; *c*,*) echo_n=-n echo_c= ;; *) echo_n= echo_c='\c' ;; esac parse_server_arguments() { for arg do case "$arg" in --basedir=*) basedir=`echo "$arg" | sed -e 's/^[^=]*=//'` bindir="$basedir/bin" if test -z "$datadir_set"; then datadir="$basedir/data" fi sbindir="$basedir/sbin" libexecdir="$basedir/libexec" ;; --datadir=*) datadir=`echo "$arg" | sed -e 's/^[^=]*=//'` datadir_set=1 ;; --user=*) user=`echo "$arg" | sed -e 's/^[^=]*=//'` ;; --pid-file=*) server_pid_file=`echo "$arg" | sed -e 's/^[^=]*=//'` ;; --service-startup-timeout=*) service_startup_timeout=`echo "$arg" | sed -e 's/^[^=]*=//'` ;; --use-mysqld_safe) use_mysqld_safe=1;; --use-manager) use_mysqld_safe=0;; esac done } parse_manager_arguments() { for arg do case "$arg" in --pid-file=*) pid_file=`echo "$arg" | sed -e 's/^[^=]*=//'` ;; --user=*) user=`echo "$arg" | sed -e 's/^[^=]*=//'` ;; esac done } wait_for_pid () { verb="$1" manager_pid="$2" # process ID of the program operating on the pid-file i=0 avoid_race_condition="by checking again" while test $i -ne $service_startup_timeout ; do case "$verb" in 'created') # wait for a PID-file to pop into existence. test -s $pid_file && i='' && break ;; 'removed') # wait for this PID-file to disappear test ! -s $pid_file && i='' && break ;; *) echo "wait_for_pid () usage: wait_for_pid created|removed manager_pid" exit 1 ;; esac # if manager isn't running, then pid-file will never be updated if test -n "$manager_pid"; then if kill -0 "$manager_pid" 2>/dev/null; then : # the manager still runs else # The manager may have exited between the last pid-file check and now. if test -n "$avoid_race_condition"; then avoid_race_condition="" continue # Check again. fi # there's nothing that will affect the file. log_failure_msg "Manager of pid-file quit without updating file." return 1 # not waiting any more. fi fi echo $echo_n ".$echo_c" i=`expr $i + 1` sleep 1 done if test -z "$i" ; then log_success_msg return 0 else log_failure_msg return 1 fi } # Get arguments from the my.cnf file, # the only group, which is read from now on is [mysqld] if test -x ./bin/my_print_defaults then print_defaults="./bin/my_print_defaults" elif test -x $bindir/my_print_defaults then print_defaults="$bindir/my_print_defaults" elif test -x $bindir/mysql_print_defaults then print_defaults="$bindir/mysql_print_defaults" else # Try to find basedir in /etc/my.cnf conf=/etc/my.cnf print_defaults= if test -r $conf then subpat='^[^=]*basedir[^=]*=\(.*\)$' dirs=`sed -e "/$subpat/!d" -e 's//\1/' $conf` for d in $dirs do d=`echo $d | sed -e 's/[ ]//g'` if test -x "$d/bin/my_print_defaults" then print_defaults="$d/bin/my_print_defaults" break fi if test -x "$d/bin/mysql_print_defaults" then print_defaults="$d/bin/mysql_print_defaults" break fi done fi # Hope it's in the PATH ... but I doubt it test -z "$print_defaults" && print_defaults="my_print_defaults" fi # # Read defaults file from 'basedir'. If there is no defaults file there # check if it's in the old (depricated) place (datadir) and read it from there # extra_args="" if test -r "$basedir/my.cnf" then extra_args="-e $basedir/my.cnf" else if test -r "$datadir/my.cnf" then extra_args="-e $datadir/my.cnf" fi fi parse_server_arguments `$print_defaults $extra_args mysqld server mysql_server mysql.server` # Look for the pidfile parse_manager_arguments `$print_defaults $extra_args manager` # # Set pid file if not given # if test -z "$pid_file" then pid_file=$datadir/mysqlmanager-`/bin/hostname`.pid else case "$pid_file" in /* ) ;; * ) pid_file="$datadir/$pid_file" ;; esac fi if test -z "$server_pid_file" then server_pid_file=$datadir/`/bin/hostname`.pid else case "$server_pid_file" in /* ) ;; * ) server_pid_file="$datadir/$server_pid_file" ;; esac fi case "$mode" in 'start') # Start daemon # Safeguard (relative paths, core dumps..) cd $basedir manager=$bindir/mysqlmanager if test -x $libexecdir/mysqlmanager then manager=$libexecdir/mysqlmanager elif test -x $sbindir/mysqlmanager then manager=$sbindir/mysqlmanager fi echo $echo_n "Starting MySQL" if test -x $manager -a "$use_mysqld_safe" = "0" then if test -n "$other_args" then log_failure_msg "MySQL manager does not support options '$other_args'" exit 1 fi # Give extra arguments to mysqld with the my.cnf file. This script may # be overwritten at next upgrade. $manager --user=$user --pid-file=$pid_file >/dev/null 2>&1 & wait_for_pid created $!; return_value=$? # Make lock for RedHat / SuSE if test -w /var/lock/subsys then touch /var/lock/subsys/mysqlmanager fi exit $return_value elif test -x $bindir/mysqld_safe then # Give extra arguments to mysqld with the my.cnf file. This script # may be overwritten at next upgrade. pid_file=$server_pid_file $bindir/mysqld_safe --datadir=$datadir --pid-file=$server_pid_file $other_args >/dev/null 2>&1 & wait_for_pid created $!; return_value=$? # Make lock for RedHat / SuSE if test -w /var/lock/subsys then touch /var/lock/subsys/mysql fi exit $return_value else log_failure_msg "Couldn't find MySQL manager ($manager) or server ($bindir/mysqld_safe)" fi ;; 'stop') # Stop daemon. We use a signal here to avoid having to know the # root password. # The RedHat / SuSE lock directory to remove lock_dir=/var/lock/subsys/mysqlmanager # If the manager pid_file doesn't exist, try the server's if test ! -s "$pid_file" then pid_file=$server_pid_file lock_dir=/var/lock/subsys/mysql fi if test -s "$pid_file" then mysqlmanager_pid=`cat $pid_file` echo $echo_n "Shutting down MySQL" kill $mysqlmanager_pid # mysqlmanager should remove the pid_file when it exits, so wait for it. wait_for_pid removed "$mysqlmanager_pid"; return_value=$? # delete lock for RedHat / SuSE if test -f $lock_dir then rm -f $lock_dir fi exit $return_value else log_failure_msg "MySQL manager or server PID file could not be found!" fi ;; 'restart') # Stop the service and regardless of whether it was # running or not, start it again. if $0 stop $other_args; then $0 start $other_args else log_failure_msg "Failed to stop running server, so refusing to try to start." exit 1 fi ;; 'reload'|'force-reload') if test -s "$server_pid_file" ; then read mysqld_pid < $server_pid_file kill -HUP $mysqld_pid && log_success_msg "Reloading service MySQL" touch $server_pid_file else log_failure_msg "MySQL PID file could not be found!" exit 1 fi ;; 'status') # First, check to see if pid file exists if test -s "$server_pid_file" ; then read mysqld_pid < $server_pid_file if kill -0 $mysqld_pid 2>/dev/null ; then log_success_msg "MySQL running ($mysqld_pid)" exit 0 else log_failure_msg "MySQL is not running, but PID file exists" exit 1 fi else # Try to find appropriate mysqld process mysqld_pid=`pidof $sbindir/mysqld` if test -z $mysqld_pid ; then if test "$use_mysqld_safe" = "0" ; then lockfile=/var/lock/subsys/mysqlmanager else lockfile=/var/lock/subsys/mysql fi if test -f $lockfile ; then log_failure_msg "MySQL is not running, but lock exists" exit 2 fi log_failure_msg "MySQL is not running" exit 3 else log_failure_msg "MySQL is running but PID file could not be found" exit 4 fi fi ;; *) # usage echo "Usage: $0 {start|stop|restart|reload|force-reload|status} [ MySQL server options ]" exit 1 ;; esac exit 0 An unimportant aside: The previous users of the machine kept a messy home directory. Their home directory was /root. I've pasted a copy at http://www.pastebin.ca/2167496. My question: Why is there a /etc/init.d/mysql file on this Slackware machine? How could it have gotten there? P.S. This question is far from perfect. Please feel free to edit it.

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  • Does my TPL partitioner cause a deadlock?

    - by Scott Chamberlain
    I am starting to write my first parallel applications. This partitioner will enumerate over a IDataReader pulling chunkSize records at a time from the data-source. protected class DataSourcePartitioner<object[]> : System.Collections.Concurrent.Partitioner<object[]> { private readonly System.Data.IDataReader _Input; private readonly int _ChunkSize; public DataSourcePartitioner(System.Data.IDataReader input, int chunkSize = 10000) : base() { if (chunkSize < 1) throw new ArgumentOutOfRangeException("chunkSize"); _Input = input; _ChunkSize = chunkSize; } public override bool SupportsDynamicPartitions { get { return true; } } public override IList<IEnumerator<object[]>> GetPartitions(int partitionCount) { var dynamicPartitions = GetDynamicPartitions(); var partitions = new IEnumerator<object[]>[partitionCount]; for (int i = 0; i < partitionCount; i++) { partitions[i] = dynamicPartitions.GetEnumerator(); } return partitions; } public override IEnumerable<object[]> GetDynamicPartitions() { return new ListDynamicPartitions(_Input, _ChunkSize); } private class ListDynamicPartitions : IEnumerable<object[]> { private System.Data.IDataReader _Input; int _ChunkSize; private object _ChunkLock = new object(); public ListDynamicPartitions(System.Data.IDataReader input, int chunkSize) { _Input = input; _ChunkSize = chunkSize; } public IEnumerator<object[]> GetEnumerator() { while (true) { List<object[]> chunk = new List<object[]>(_ChunkSize); lock(_Input) { for (int i = 0; i < _ChunkSize; ++i) { if (!_Input.Read()) break; var values = new object[_Input.FieldCount]; _Input.GetValues(values); chunk.Add(values); } if (chunk.Count == 0) yield break; } var chunkEnumerator = chunk.GetEnumerator(); lock(_ChunkLock) //Will this cause a deadlock? { while (chunkEnumerator.MoveNext()) { yield return chunkEnumerator.Current; } } } } IEnumerator IEnumerable.GetEnumerator() { return ((IEnumerable<object[]>)this).GetEnumerator(); } } } I wanted IEnumerable object it passed back to be thread safe (the .Net example was so I am assuming PLINQ and TPL could need it) will the lock on _ChunkLock near the bottom help provide thread safety or will it cause a deadlock? From the documentation I could not tell if the lock would be released on the yeld return. Also if there is built in functionality to .net that will do what I am trying to do I would much rather use that. And if you find any other problems with the code I would appreciate it.

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  • March 21st Links: ASP.NET, ASP.NET MVC, AJAX, Visual Studio, Silverlight

    - by ScottGu
    Here is the latest in my link-listing series. If you haven’t already, check out this month’s "Find a Hoster” page on the www.asp.net website to learn about great (and very inexpensive) ASP.NET hosting offers.  [In addition to blogging, I am also now using Twitter for quick updates and to share links. Follow me at: twitter.com/scottgu] ASP.NET URL Routing in ASP.NET 4: Scott Mitchell has a nice article that talks about the new URL routing features coming to Web Forms applications with ASP.NET 4.  Also check out my previous blog post on this topic. Control of Web Control ClientID Values in ASP.NET 4: Scott Mitchell has a nice article that describes how it is now easy to control the client “id” value emitted by server controls with ASP.NET 4. Web Deployment Made Awesome: Very nice MIX10 talk by Scott Hanselman on the new web deployment features coming with VS 2010, MSDeploy, and .NET 4.  Makes deploying web applications much, much easier. ASP.NET 4’s Browser Capabilities Support: Nice blog post by Stephen Walther that talks about the new browser definition capabilities support coming with ASP.NET 4. Integrating Twitter into an ASP.NET Website: Nice article by Scott Mitchell that demonstrates how to call and integrate Twitter from within your ASP.NET applications. Improving CSS with .LESS: Nice article by Scott Mitchell that describes how to optimize CSS using .LESS – a free, open source library. ASP.NET MVC Upgrading ASP.NET MVC 1 applications to ASP.NET MVC 2: Eilon Lipton from the ASP.NET team has a nice post that describes how to easily upgrade your ASP.NET MVC 1 applications to ASP.NET MVC 2.  He has an automated tool that makes this easy. Note that automated MVC upgrade support is also built-into VS 2010.  Use the tool in this blog post for updating existing MVC projects using VS 2008. Advanced ASP.NET MVC 2: Nice video talk by Brad Wilson of the ASP.NET MVC team.  In it he describes some of the more advanced features in ASP.NET MVC 2 and how to maximize your productivity with them. Dynamic Select Lists with ASP.NET MVC and jQuery: Michael Ceranski has a nice blog post that describes how to dynamically populate dropdownlists on the client using AJAX. AJAX Microsoft AJAX Minifier: We recently shipped an updated minifier utility that allows you to shrink/minify both JavaScript and CSS files – which can improve the performance of your web applications.  You can run this either manually as a command-line tool or now automatically integrate it using a Visual Studio build task.  You can download it for free here. Visual Studio VS 2010 Tip: Quickly Closing Documents: Nice blog post that describes some techniques for optimizing how windows are closed with the new VS 2010 IDE. Collpase to Definitions with Outlining: Nice tip from Zain on how to collapse your code editor to outline mode using Ctrl + M, Ctrl + O.  Also check out his post on copy/paste with outlining here. $299 VS 2010 Upgrade Offer for VS 2005/2008 Standard Users: Soma blogs about a nice VS 2010 upgrade offer you can take advantage of if you have VS 2005 or VS 2008 Standard editions.  For $299 you can upgrade to VS 2010 Professional edition. Dependency Graphics: Jason Zander (who runs the VS team) has a nice blog post that covers the new dependency graph support within VS 2010.  This makes it easier to visualize the dependencies within your application.  Also check out this video here. Layer Validation: Jason Zander has a nice blog post that talks about the new layer validation features in VS 2010.  This enables you to enforce cleaner layering within your projects and solutions.  VS 2010 Profiler Blog: The VS 2010 Profiler Team has their own blog and on it you can find a bunch of nice posts from the last few months that talk about a lot of the new features coming with VS 2010’s Profiler support.  Some really nice features coming. Silverlight Silverlight 4 Training Course: Nice free set of training courses from Microsoft that can help bring you up to speed on all of the new Silverlight 4 features and how to build applications with them.  Updated and current with the recently released Silverlight 4 RC build and tools. Getting Started with Silverlight and Windows Phone 7 Development: Nice blog post by Tim Heuer that summarizes how to get started building Windows Phone 7 applications using Silverlight.  Also check out my blog post from last week on how to build a Windows Phone 7 Twitter application using Silverlight. A Guide to What Has Changed with the Silverlight 4 RC: Nice summary post by Tim Heuer that describes all of the things that have changed between the Silverlight 4 Beta and the Silverlight 4 RC. Path Based Layout - Part 1 and Part 2: Christian Schormann has a nice blog post about a really cool new feature in Expression Blend 4 and Silverlight 4 called Path Layout. Also check out Andy Beaulieu’s blog post on this. Hope this helps, Scott

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  • Watch the Silverlight 4 Launch event and LIVE QA with ScottGu and others

    Next week on 13-April at 8:00 AM PST Scott Guthrie will deliver a keynote address for the DevConnections conference being held in Las Vegas, NV. Scott will provide updates on the progress made in Silverlight 4 and will provide the details of availability of the developer tools, runtime and other news. Mark your calendars and return to the Silverlight community site to tune into the LIVE event. After the keynote, Channel 9 will be hosting interviews with Scott and other key members of the Silverlight...Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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  • How to enable customers to use their own domain for sites hosted by me

    - by Scott
    I am thinking of running a self-site builder. But was wondering how would I allow customers to use their own domains that they already own. Is that even possible? Let's say my site is www.bestsitebuildingwebsite.com and each customer has urls like this www.bestsitebuildingwebsite.com/frances www.bestsitebuildingwebsite.com/eden www.bestsitebuildingwebsite.com/john And a customer has a domain called widgets.com Is it actually possible domain widgets.com to go to my site somehow and have HASHES on the URL still work (my site makes use of hashes for AJAX queries). And their site still have good SEO with Google? Thanks Scott

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  • Would a multitouch capable PC allow me to do Android development simulating the touch UI without an Android device ?

    - by Scott Davies
    Hi, I recently purchased a Samsung Galaxy Tab as a reference implementation (phone and first gen Android tablet), of Android 2.x for app development. I have noticed a slew of Android 3.0 slates being talked about at CES 2011 (Motorola XOOM, etc.). If I had a multitouch PC with the Android SDK/Emulator on it, would this allow me to more closely approximate device simulation by allowing user input via the multitouch screen ? Would it work via touch just like Windows 7 recognizes touch as mouse style input ? Has anyone done this ? Thanks, Scott

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  • DevIntersection Conference Dec 9th-12th

    - by ScottGu
    I’m excited to be presenting a keynote at the DevIntersection conference this coming Dec 9th->12th in Las Vegas.  This conference has an awesome set of speakers from a variety of backgrounds.  A number of people from my team (including Scott Hanselman, Scott Hunter and Daniel Roth from the ASP.NET team) will be presenting in addition to me.  You can learn more about the conference and check out the schedule here. Attendees who register by November 20th will receive a free Windows 8 Tablet – so if you are interested in attending sign-up soon! Hope to see some of you there, Scott

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  • Watch Ask the Gu on Channel 9 Live

    Scott Guthrie was kind enough to join the Channel 9 Live crew for an discussion of everything Silverlight immediately following his Silverlight 4 launch keynote. You can check out the recorded video right on Channel 9. Scott does a great job fielding the questions from the audience and from Twitter. Charles Torre is a great moderator he asks some great questions in addition to the flurry that came in from Twitter. I love when he asks Scott how we can release Silverlight versions at such a fast...Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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  • Data Source Security Part 5

    - by Steve Felts
    If you read through the first four parts of this series on data source security, you should be an expert on this focus area.  There is one more small topic to cover related to WebLogic Resource permissions.  After that comes the test, I mean example, to see with a real set of configuration parameters what the results are with some concrete values. WebLogic Resource Permissions All of the discussion so far has been about database credentials that are (eventually) used on the database side.  WLS has resource credentials to control what WLS users are allowed to access JDBC resources.  These can be defined on the Policies tab on the Security tab associated with the data source.  There are four permissions: “reserve” (get a new connection), “admin”, “shrink”, and reset (plus the all-inclusive “ALL”); we will focus on “reserve” here because we are talking about getting connections.  By default, JDBC resource permissions are completely open – anyone can do anything.  As soon as you add one policy for a permission, then all other users are restricted.  For example, if I add a policy so that “weblogic” can reserve a connection, then all other users will fail to reserve connections unless they are also explicitly added.  The validation is done for WLS user credentials only, not database user credentials.  Configuration of resources in general is described at “Create policies for resource instances” http://docs.oracle.com/cd/E24329_01/apirefs.1211/e24401/taskhelp/security/CreatePoliciesForResourceInstances.html.  This feature can be very useful to restrict what code and users can get to your database. There are the three use cases: API Use database credentials User for permission checking getConnection() True or false Current WLS user getConnection(user,password) False User/password from API getConnection(user,password) True Current WLS user If a simple getConnection() is used or database credentials are enabled, the current user that is authenticated to the WLS system is checked. If database credentials are not enabled, then the user and password on the API are used. Example The following is an actual example of the interactions between identity-based-connection-pooling-enabled, oracle-proxy-session, and use-database-credentials. On the database side, the following objects are configured.- Database users scott; jdbcqa; jdbcqa3- Permission for proxy: alter user jdbcqa3 grant connect through jdbcqa;- Permission for proxy: alter user jdbcqa grant connect through jdbcqa; The following WebLogic Data Source objects are configured.- Users weblogic, wluser- Credential mapping “weblogic” to “scott”- Credential mapping "wluser" to "jdbcqa3"- Data source descriptor configured with user “jdbcqa”- All tests are run with Set Client ID set to true (more about that below).- All tests are run with oracle-proxy-session set to false (more about that below). The test program:- Runs in servlet- Authenticates to WLS as user “weblogic” Use DB Credentials Identity based getConnection(scott,***) getConnection(weblogic,***) getConnection(jdbcqa3,***) getConnection()  true  true Identity scottClient weblogicProxy null weblogic fails - not a db user User jdbcqa3Client weblogicProxy null Default user jdbcqaClient weblogicProxy null  false  true scott fails - not a WLS user User scottClient scottProxy null jdbcqa3 fails - not a WLS user User scottClient scottProxy null  true  false Proxy for scott fails weblogic fails - not a db user User jdbcqa3Client weblogicProxy jdbcqa Default user jdbcqaClient weblogicProxy null  false  false scott fails - not a WLS user Default user jdbcqaClient scottProxy null jdbcqa3 fails - not a WLS user Default user jdbcqaClient scottProxy null If Set Client ID is set to false, all cases would have Client set to null. If this was not an Oracle thin driver, the one case with the non-null Proxy in the above table would throw an exception because proxy session is only supported, implicitly or explicitly, with the Oracle thin driver. When oracle-proxy-session is set to true, the only cases that will pass (with a proxy of "jdbcqa") are the following.1. Setting use-database-credentials to true and doing getConnection(jdbcqa3,…) or getConnection().2. Setting use-database-credentials to false and doing getConnection(wluser, …) or getConnection(). Summary There are many options to choose from for data source security.  Considerations include the number and volatility of WLS and Database users, the granularity of data access, the depth of the security identity (property on the connection or a real user), performance, coordination of various components in the software stack, and driver capabilities.  Now that you have the big picture (remember that table in part 1), you can make a more informed choice.

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  • which xml validator will work perfectly for multithreading project

    - by Sunil Kumar Sahoo
    Hi All, I have used jdom for xml validation against schema. The main problem there is that it gives an error FWK005 parse may not be called while parsing The main reason was that multiple of threads working for xerces validation at the same time. SO I got the solution that i have to lock that validation. which is not good So I want to know which xml validator works perfectly for multithreading project public static HashMap validate(String xmlString, Validator validator) { HashMap<String, String> map = new HashMap<String, String>(); long t1 = System.currentTimeMillis(); DocumentBuilder builder = null; try { //obtain lock to proceed // lock.lock(); try { builder = DocumentBuilderFactory.newInstance().newDocumentBuilder(); // Source source = new DOMSource(builder.parse(new ByteArrayInputStream(xmlString.getBytes()))); validator.validate(new StreamSource(new StringReader(xmlString))); map.put("ISVALID", "TRUE"); logger.info("We have successfuly validated the schema"); } catch (Exception ioe) { ioe.printStackTrace(); logger.error("NOT2 VALID STRING IS :" + xmlString); map.put("MSG", ioe.getMessage()); // logger.error("IOException while validating the input XML", ioe); } logger.info(map); long t2 = System.currentTimeMillis(); logger.info("XML VALIDATION TOOK:::" + (t2 - t1)); } catch (Exception e) { logger.error(e); } finally { //release lock // lock.unlock(); builder = null; } return map; } Thanks Sunil Kumar Sahoo

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  • ADO.NET DataTable/DataRow Thread Safety

    - by Allen E. Scharfenberg
    Introduction A user reported to me this morning that he was having an issue with inconsistent results (namely, column values sometimes coming out null when they should not be) of some parallel execution code that we provide as part of an internal framework. This code has worked fine in the past and has not been tampered with lately, but it got me to thinking about the following snippet: Code Sample lock (ResultTable) { newRow = ResultTable.NewRow(); } newRow["Key"] = currentKey; foreach (KeyValuePair<string, object> output in outputs) { object resultValue = output.Value; newRow[output.Name] = resultValue != null ? resultValue : DBNull.Value; } lock (ResultTable) { ResultTable.Rows.Add(newRow); } (No guarantees that that compiles, hand-edited to mask proprietery information.) Explanation We have this cascading type of locking code other places in our system, and it works fine, but this is the first instance of cascading locking code that I have come across that interacts with ADO .NET. As we all know, members of framework objects are usually not thread safe (which is the case in this situation), but the cascading locking should ensure that we are not reading and writing to ResultTable.Rows concurrently. We are safe, right? Hypothesis Well, the cascading lock code does not ensure that we are not reading from or writing to ResultTable.Rows at the same time that we are assigning values to columns in the new row. What if ADO .NET uses some kind of buffer for assigning column values that is not thread safe--even when different object types are involved (DataTable vs. DataRow)? Has anyone run into anything like this before? I thought I would ask here at StackOverflow before beating my head against this for hours on end :) Conclusion Well, the consensus appears to be that changing the cascading lock to a full lock has resolved the issue. That is not the result that I expected, but the full lock version has not produced the issue after many, many, many tests. The lesson: be wary of cascading locks used on APIs that you do not control. Who knows what may be going on under the covers!

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