<style type='text/css'> table { border-style: solid; border-width: 1px; border-collapse: collapse; } td { border-style: solid; border-width: 1px; padding: 4px; } </style> </head> <body> <h1>PyBat Readme</h1> <ul> <li><a href="#about">About PyBat</a></li> <li><a href="#install">Installation</a></li> <li><a href="#test">Self Test</a></li> <li><a href="#req">Requirements</a></li> <li><a href="#p2b">Calling a Batch File from a Python Script</a></li> <li><a href="#b2p">Calling a Python Script from a Batch File</a></li> <li><a href="#p2p">Calling a Python Script from a Python Script</a></li> </ul> <h3><a name="about">About PyBat</a></h3> PyBat is a python module and batch file that allow you to share environment variable changes between Python scripts and batch files. The original problem comes from the fact that when the batch file's cmd.exe process calls the Python script's python.exe process (or vice versa), any changes to the environment variables in the child process won't be reflected in the parent.<br/> NOTE: You only need to use PyBat when the called batch file/python script makes environment variable changes that need to be reflected in the calling process. <h3><a name="install">Installation</a></h3> Unzip the pybat.py and pybat.bat scripts to the same directory. Set the %PYCMD% environment variable on your system to point to the python.exe interpreter, or leave %PYCMD% blank if Windows is setup it run *.py files from the command-line (it usually is). <h3><a name="test">Self Test</a></h3> Unzip the other files in the download to the directory with pybat.py and pybat.bat. Run pybat_test.bat to perform the self-test. <h3><a name="req">Requirements</a></h3> <p>Both the pybat.bat and pybat.py need to be able to write to the directory that they are located in. Pybat uses 32-bit exit codes, so Windows NT or later is required. You must have the Python 2.4 or later installed.</p> <p>Although PyBat does have measures to deal with concurrency issues, a multi-threaded Python script should not call a batch file through PyBat because any environment variable changes made by the script in between calling and returning from the <code>pybat.callbat()</code> function will be overwritten by the environment variables in the batch file.</p> <h3><a name="p2b">Calling a Batch File from a Python Script</a></h3> In the Python script, you must import pybat and call the batch file with the <code>callbat()</code> function. Remember that if the batch file's filepath has spaces, it must be enclosed in double-quotes. <blockquote><code>import pybat<br/> pybat.callbat('foobar.bat arg1 arg2')<br/> pybat.callbat('"C:\\Program Files\\barfoo.bat" arg1 arg2')<br/> </code></blockquote> The return value of callbat() is the exit code of the batch file that was run. <h3><a name="b2p">Calling a Python Script from a Batch File</a></h3> In the batch file, make a call to pybat.bat and pass the python script's filepath and arguments to it. Be sure to use double-quotes if the python script's filepath has spaces. <blockquote><code>call pybat.bat foobar.py arg1 arg2<br/> call pybat.bat "c:\program files\foobar.py" arg1 arg2<br/> </code></blockquote> The value of %ERRORLEVEL% is set to the exit code of the Python script. <h3><a name="p2p">Calling a Python Script from a Python Script</a></h3> It is recommended to use Python's <code>execfile()</code> function to run other scripts. However, if you must share environment variables and pass the command-line arguments, use Pybat's <code>callpy()</code> function.<br/> Import the pybat module and call <code>callpy()</code> with the script name and command-line arguments.<br/> <blockquote><code>import pybat<br/> pybat.callpy('foobar.py arg1 arg2')</code></blockquote>