-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 10/25/2011 03:21 PM, Adam Williamson wrote: > On Tue, 2011-10-25 at 20:39 +0200, Michał Piotrowski wrote: >> 2011/10/25 Richard W.M. Jones <rjones@xxxxxxxxxx>: >>> On Tue, Oct 25, 2011 at 08:33:28PM +0200, Michał Piotrowski >>> wrote: >>>> 2011/10/25 Chris Adams <cmadams@xxxxxxxxxx>: >>>>> Once upon a time, Michał Piotrowski <mkkp4x4@xxxxxxxxx> >>>>> said: >>>>>> I created feature page >>>>>> https://fedoraproject.org/wiki/Features/F18MorePortableInterpreters >>>>> >>>>> >>>>>> I strongly object to this "feature". /bin/sh is a Unix standard back to >>>>> IIRC around 7th Edition, and there is NO good reason to >>>>> break it. The "#!/usr/bin/env foo" suggested replacement >>>>> has always been a hack to work around broken systems, not >>>>> something suggested for all scripts. >>>> >>>> What is wrong with #!/usr/bin/env interpreter from technical >>>> POV? >>> >>> This is what's wrong: >>> >>> $ cat > sh.sh #!/bin/sh $ cat > env.sh #!/usr/bin/env sh $ >>> chmod +x sh.sh env.sh $ time for i in $(seq 1000); do ./sh.sh; >>> done >>> >>> real 0m2.737s user 0m0.750s sys >>> 0m1.519s $ time for i in $(seq 1000); do ./env.sh; done >>> >>> real 0m3.677s user 0m1.013s sys >>> 0m2.296s >>> >> >> Yeah, it is noticeably slower - about 0,00094s. > > Uh. ~2.7secs vs. ~3.7 secs is nearly one entire second, not one > tiny tiny fraction of a second, isn't it? There are also possible Security ramifications of allowing the interpreter to be replaced, users could stumble upon this. Python even tries to prevent this with the -Es qualifier. man python ... -s Don't add user site directory to sys.path. -E Ignore environment variables like PYTHONPATH and PYTHONHOME that modify the behavior of the interpreter. I think putting #!/usr/bin/env interpreter is a very bad idea for administrative tools. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAk6nDZ0ACgkQrlYvE4MpobNN3QCdG3620U65PBvuls1KPkZHWCLm T5EAoK4Vpm41pYxpMZty3hF/bJsBg/nx =no7E -----END PGP SIGNATURE----- -- devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxxx https://admin.fedoraproject.org/mailman/listinfo/devel
