ipcmd - Command-line interface to XSI (SysV) semaphores and message queues
==========================================================================

ipcmd exposes the XSI (SysV) semaphore and message queues APIs through a
simple command-line interface, enabling scriptable interprocess communication
and synchronization with usually no configuration required. 

SUPPORTED PLATFORMS
===================

ipcmd should compile and run on any platform that supports SysV IPC. It has
specifically been tested on Solaris 10, FreeBSD 8.2, Mac OS X 10.6, RHEL 5.4,
and Cygwin 1.7.9-1.

ipcmd currently supports only the standard XSI APIs, and not any
vendor-specific extensions.

CONTENTS
========

CHANGES   - Visible changes in the current version and previous versions
LICENSE   - The BSD license
Makefile  - POSIX Makefile
README    - This file containing basic information & installation instructions
bin/      - Destination of the ipcmd executable when building with "make"
examples/ - Examples that illustrate the use of ipcmd
man/      - Contains the ipcmd man page
src/      - ipcmd source code
test/     - Test scripts that can be run with "make check" after building ipcmd
    
INSTALLATION
============

1. (Optional) The default Makefile should work on a POSIX-compliant system, 
   but it can be edited to choose a specific compiler or compiler flags.

2. Issue the following commands to build and test ipcmd:

    make
    make check 

3. Move the contents of the bin/ and man/ directories to a location in your
   PATH and MANPATH, respectively.

CONFIGURATION
=============

The default system limits are usually adequate for semaphores. 

The default message queue limits for most current platforms prohibit messages
larger than a few kilobytes. See your system's documentation on how to
increase those limits.

On Cygwin, Cygserver must be running (it is not by default). See:
http://www.cygwin.com/cygwin-ug-net/using-cygserver.html
for details.

USAGE
=====

ipcmd is provided as a single executable that supports multiple subcommands.
To get a list of supported subcommands, type:

    ipcmd

To get help with a specific subcommand, type:

    ipcmd SUBCOMMAND -h

Where SUBCOMMAND is the subcommand of interest.

See the manual page, web site, and examples in the examples/ directory for
more information.

WEB SITE
========

    http://code.google.com/p/ipcmd/

KNOWN ISSUES
============

Mac OS X 10.6 is unable to perform an array of more than 5 semaphore
operations. This issue has been reported to Apple.

While ipcmd should be stable enough for production use, there may some
interface instability with respect to the semaphore interval notation used by
"ipcmd semop" and "ipcmd semctl setall". See the TODO file for additional
notes (suggestions are welcomed!).

BUGS
====

Please report any bugs in the bug tracker at the web site, or email the
author, Nathan Weeks (weeks at iastate dot edu).