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Full Discussion: Environment Variables in Shebangs
Top Forums Shell Programming and Scripting Environment Variables in Shebangs Post 302142374 by drl on Thursday 25th of October 2007 08:19:27 PM
Old 10-25-2007
Hi.

I have an alternate suggestion. The problem you cite has been one of the thorns in the side of portability for a long time.

The perl folks early on published a script that would reset the shebang line to the local path.

Here's an example of fixing a python script that has only "python2.3" has the path:
Code:
#!/usr/bin/env sh

# @(#) s1       Demonstrate fixing the shebang line.

set -o nounset
echo

debug=":"
debug="echo"

## Use local command version for the commands in this demonstration.

echo "(Versions displayed with local utility \"version\")"
version >/dev/null 2>&1 && version bash fixin my-nl

# Stage erroneous script.
cp py0 py1

echo

echo " Original python script:"
my-nl py1

echo
echo " Attempt to run will fail:"
./py1

echo
echo " Results of fixin running on py1:"
fixin py1
my-nl py1
echo
./py1

exit 0

Producing:
Code:
% ./s1

(Versions displayed with local utility "version")
GNU bash 2.05b.0
fixin (local) 293
my-nl (local) 293

 Original python script:

==> py1 <==

  1 #!python2.3
  2
  3 # @(#) py1  Demonstrate python feature.
  4
  5 print ' Hello, world from python.'

 Attempt to run will fail:
./s1: ./py1: python2.3: bad interpreter: No such file or directory

 Results of fixin running on py1:
Changing py1 to /usr/bin/python2.3

==> py1 <==

  1 #!/usr/bin/python2.3
  2
  3 # @(#) py1  Demonstrate python feature.
  4
  5 print ' Hello, world from python.'

 Hello, world from python.

cheers, drl
 

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LEARN ABOUT DEBIAN

irunner

IRUNNER(1)																IRUNNER(1)

NAME

       irunner - interactive runner interface

SYNOPSIS

       irunner [options] file_to_run

DESCRIPTION

       irunner	is  an	interface to the various interactive runners available in IPython's irunner module.  It can used to run scripts as if they
       where typed up interactively.

       The already implemented runners are listed below; adding one for a new program is a trivial task, see the source for examples.

OPTIONS

       -h, --help
	      show this help message and exit

       --ipython
	      IPython interactive runner (default).

       --python
	      Python interactive runner.

       --sage SAGE interactive runner.

EXAMPLE

       irunner.py --python -- --help will pass --help to the python runner.  Similarly, irunner.py --ipython -- --interact script.ipy

SEE ALSO

       ipython(1)

AUTHOR

       irunner	 is   an   extension   of   Ken   Schutte   <kschutte-AT-csail.mit.edu>'s   script   contributed   on	the   ipython-user   list:
       http://mail.scipy.org/pipermail/ipython-user/2006-May/003539.html

       This  manual  page  was written by Bernd Zeimetz <bernd@bzed.de>, for the Debian project (but may be used by others).  Modified by Fernando
       Perez <Fernando.Perez@berkeley.edu> for inclusion in IPython.

								   July 15, 2011							IRUNNER(1)
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