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Full Discussion: Unix message Queue
Top Forums UNIX for Advanced & Expert Users Unix message Queue Post 38919 by Perderabo on Wednesday 30th of July 2003 11:12:50 AM
Old 07-30-2003
Hmmm....you do have a point. I was getting CBYTES mixed up with QBYTES.

I agree, for the most part, QNUM = 0 and CBYTES != 0 is not consistent. But I can think of one exception where it might make sense. When you do your msgsnd, you are setting msgflg to zero. That means that IPC_NOWAIT is turned off. The msgsnd system call checks to see if this message would exceed some limits. This includes a check of the message queue you are using as well as some system wide limits. If a msgsnd would exceed a limit and it did not set IPC_NOWAIT, the msgsnd system call will suspend until it is safe to send the message. I don't know what state the message queue is in during this suspension. It could well be that CBYTES has been increased but QNUM has not yet been incremented.

This would explain why it works for a few hours and then locks up. Reproduce the error and then run "ipcs -qa" and compare the total messages queue resources in use against your kernel parameters. If this is the problem, you will need to increase the kernel parameters. Or you may have a message queue leak somewhere.

That is my only idea. If it's not that, I would next suspect a broken kernel. You might check for any appropiate patches.
 

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GIT-SH-SETUP(1) 						    Git Manual							   GIT-SH-SETUP(1)

NAME
git-sh-setup - Common git shell script setup code SYNOPSIS
. "$(git --exec-path)/git-sh-setup" DESCRIPTION
This is not a command the end user would want to run. Ever. This documentation is meant for people who are studying the Porcelain-ish scripts and/or are writing new ones. The git sh-setup scriptlet is designed to be sourced (using .) by other shell scripts to set up some variables pointing at the normal git directories and a few helper shell functions. Before sourcing it, your script should set up a few variables; USAGE (and LONG_USAGE, if any) is used to define message given by usage() shell function. SUBDIRECTORY_OK can be set if the script can run from a subdirectory of the working tree (some commands do not). The scriptlet sets GIT_DIR and GIT_OBJECT_DIRECTORY shell variables, but does not export them to the environment. FUNCTIONS
die exit after emitting the supplied error message to the standard error stream. usage die with the usage message. set_reflog_action set the message that will be recorded to describe the end-user action in the reflog, when the script updates a ref. git_editor runs an editor of user's choice (GIT_EDITOR, core.editor, VISUAL or EDITOR) on a given file, but error out if no editor is specified and the terminal is dumb. is_bare_repository outputs true or false to the standard output stream to indicate if the repository is a bare repository (i.e. without an associated working tree). cd_to_toplevel runs chdir to the toplevel of the working tree. require_work_tree checks if the current directory is within the working tree of the repository, and otherwise dies. require_work_tree_exists checks if the working tree associated with the repository exists, and otherwise dies. Often done before calling cd_to_toplevel, which is impossible to do if there is no working tree. require_clean_work_tree <action> [<hint>] checks that the working tree and index associated with the repository have no uncommitted changes to tracked files. Otherwise it emits an error message of the form Cannot <action>: <reason>. <hint>, and dies. Example: require_clean_work_tree rebase "Please commit or stash them." get_author_ident_from_commit outputs code for use with eval to set the GIT_AUTHOR_NAME, GIT_AUTHOR_EMAIL and GIT_AUTHOR_DATE variables for a given commit. GIT
Part of the git(1) suite Git 1.7.10.4 11/24/2012 GIT-SH-SETUP(1)
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