-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 According to Joshua White on 9/20/2009 9:46 AM: > The '+' option appears not to be working as documented. From the man page: > "If the first character of N (the number of bytes or lines) is a ‘+’, print > beginning with the Nth item from the start of each file, otherwise, print > the last N items in the file." I recall this working in previous versions.
Not a bug, but a difference in various versions of POSIX. From the NEWS file: > A few usages still have behavior that depends on which POSIX standard is > being conformed to, and portable applications should beware these > problematic usages. These include: > > Problematic Standard-conforming replacement, depending on > usage whether you prefer the behavior of: > POSIX 1003.2-1992 POSIX 1003.1-2001 > sort +4 sort -k 5 sort ./+4 > tail +4 tail -n +4 tail ./+4 > tail - f tail f [see (*) below] > tail -c 4 tail -c 10 ./4 tail -c4 > touch 12312359 f touch -t 12312359 f touch ./12312359 f > uniq +4 uniq -s 4 uniq ./+4 > > (*) "tail - f" does not conform to POSIX 1003.1-2001; to read > standard input and then "f", use the command "tail -- - f". You can also change behavior on the fly; read 'info coreutils standards', which states: > The GNU utilities normally conform to the version of POSIX that is > standard for your system. To cause them to conform to a different > version of POSIX, define the `_POSIX2_VERSION' environment variable to > a value of the form YYYYMM specifying the year and month the standard > was adopted. Two values are currently supported for `_POSIX2_VERSION': > `199209' stands for POSIX 1003.2-1992, and `200112' stands for POSIX > 1003.1-2001. For example, if you have a newer system but are running > software that assumes an older version of POSIX and uses `sort +1' or > `tail +10', you can work around any compatibility problems by setting > `_POSIX2_VERSION=199209' in your environment. > tail (GNU coreutils) 6.10 Consider upgrading; the latest stable version is 7.6, and has some fixes in tail. - -- Don't work too hard, make some time for fun as well! Eric Blake [email protected] -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (Cygwin) Comment: Public key at home.comcast.net/~ericblake/eblake.gpg Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAkq2lfQACgkQ84KuGfSFAYCGXACgzw0LfLpCpaxT6lSqiZLKGQrO TroAnR6T2lDf4j5fCRD6JrsKfK3Av1zV =qjk3 -----END PGP SIGNATURE-----
