On 9/03/2011 1:43 PM, Glenn Linderman wrote:
I'm of the opinion that attempting to parse a Unix #! line, and intuit what would be the equivalent on Windows is unnecessarily complex and error prone, and assumes that the variant systems are configured using the same guidelines (which the Python community may espouse, but may not be followed by all distributions, sysadmins, or users). That's why I propose a different line for Windows... it is as simple as the long-proven Unix #! line, but imposes no restrictions on or requirements that there be a #! line; it has more flexibility in that it could invoke different versions or provide different options on Unix and Windows if necessary for some environments.
#!/usr/bin/env python2.6 -B #@c:\python26\python2.6.exe
or
#!/usr/bin/python2.5 #@"C:\Program Files (x86)\IronPython 2.6 for .NET 4.0\ipy.exe"
I don't think that buys us much. A script with "#!/usr/bin/env python" could be distributed with an expectation it will work across various different machines (and possibly even different operating systems). A script with "c:\..." could not be distributed and expected to work reliably anywhere. ie, any script with a #! line (or even a #@ line) with a fully qualified Windows path can only be expected to work on a single machine - so there is no need to support both #! and #@ as the script is not even cross-machine portable, let alone cross-platform portable. The only way to expect a #! line to work across machines would be to have a "virtual" path - eg just "python2.6" without any path specifier at all. In that case, I see no problem with reusing the #! from *nix systems and treating "/usr/bin" etc as a "virtual" specifier on Windows. If people find a need on Windows to add a fully-qualified path to this line (whatever the spelling), they are implicitly saying this script works only on the current machine. IOW, as soon as someone has: #!/usr/bin/env python2.6 -B #@c:\python26\python2.6.exe in their script, the script is targeted at exactly 1 specific machine, so why not just reuse the #! syntax? OTOH, if an existing script has: #!/usr/bin/env python2.6 -B They are attempting to declare in a portable way that Python 2.6 is necessary - so why force them to add a #@ line to make it work on Windows when the #! line is the only clue Windows needs to make it work automagically? Cheers, Mark