Python execution problem

[mailpitches]

Using OSX 10.4.5

This is more of a unix/tcsh question than a python question.
Somehow I got to the point where I have two files 'a.py' and 'b.py'
which have identical contents and permissions, but one refuses to
execute:

[blah:/Library/WebServer/CGI-Executables] me% a.py
tcsh: a.py: Command not found.
[blah:/Library/WebServer/CGI-Executables] me% b.py
okay
[blah:/Library/WebServer/CGI-Executables] me%

Could someone enlighten me about how the shell knows to execute a
script? I always assumed it was just the extension, but this seems to
prove me wrong.

tnx>mp

 

[Jeffrey Schwab]

Using OSX 10.4.5

This is more of a unix/tcsh question than a python question.
Somehow I got to the point where I have two files 'a.py' and 'b.py'
which have identical contents and permissions, but one refuses to
execute:

[blah:/Library/WebServer/CGI-Executables] me% a.py
tcsh: a.py: Command not found.
[blah:/Library/WebServer/CGI-Executables] me% b.py
okay
[blah:/Library/WebServer/CGI-Executables] me%

Could someone enlighten me about how the shell knows to execute a
script? I always assumed it was just the extension, but this seems to
prove me wrong.

It checks each directory in your path for an executable file with the
name you specified. Each file has a set of associated bits to tell
whether it is executable (or readable or writable), and by whom. To add
execute permission to a.py, try this:

chmod +x a.py

FYI, it's not a great idea to rely on the current directory (.) being in
your path. You might want to type it explicitly, e.g ./a.py instead of
a.py.