diff options
Diffstat (limited to 'doc/grep.texi')
| -rw-r--r-- | doc/grep.texi | 15 |
1 files changed, 9 insertions, 6 deletions
diff --git a/doc/grep.texi b/doc/grep.texi index 890ba1b2..da103c49 100644 --- a/doc/grep.texi +++ b/doc/grep.texi @@ -935,12 +935,8 @@ follow file names must be treated as file names; by default, such options are permuted to the front of the operand list and are treated as options. -Also, -@sc{posix.2} requires that unrecognized options be diagnosed as ``illegal'', -but since they are not really against the law the default -is to diagnose them as ``invalid''. -@code{POSIXLY_CORRECT} also disables @code{_@var{N}_GNU_nonoption_argv_flags_}, -described below. +Also, @code{POSIXLY_CORRECT} disables special handling of an +invalid bracket expression. @xref{invalid-bracket-expr}. @item _@var{N}_GNU_nonoption_argv_flags_ @vindex _@var{N}_GNU_nonoption_argv_flags_ @r{environment variable} @@ -1269,6 +1265,13 @@ encoding, whereas the former is independent of locale and character set. part of the symbolic names, and must be included in addition to the brackets delimiting the bracket expression.) +@anchor{invalid-bracket-expr} +If you mistakenly omit the outer brackets, and search for say, @samp{[:upper:]}, +GNU @command{grep} prints a diagnostic and exits with status 2, on +the assumption that you did not intend to search for the nominally +equivalent regular expression: @samp{[:epru]}. +Set the @code{POSIXLY_CORRECT} environment variable to disable this feature. + Most meta-characters lose their special meaning inside bracket expressions. @table @samp |