I want to get the explanation for
! option (which means exclude) in
find command in the
And then I press
shift + 1 , a
Non-match popped out, instead of
So my question is how to search for
! in a manpage?
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man pager is
less. If you look at
less's help (press
h while in it), you'll see:
SEARCHING /pattern * Search forward for (N-th) matching line. ?pattern * Search backward for (N-th) matching line. n * Repeat previous search (for N-th occurrence). N * Repeat previous search in reverse direction. ESC-n * Repeat previous search, spanning files. ESC-N * Repeat previous search, reverse dir. & spanning files. ESC-u Undo (toggle) search highlighting. &pattern * Display only matching lines --------------------------------------------------- A search pattern may be preceded by one or more of: ^N or ! Search for NON-matching lines.
/pattern Search forward in the file for the N-th line containing the pat‐ tern. N defaults to 1. The pattern is a regular expression, as recognized by the regular expression library supplied by your system. The search starts at the first line displayed (but see the -a and -j options, which change this). Certain characters are special if entered at the beginning of the pattern; they modify the type of search rather than become part of the pattern: ^N or ! Search for lines which do NOT match the pattern.
So, a pattern of just
! is an empty pattern (which matches anything) negated - so nothing will match it.
You'll have to escape the significance of
! at the start of a pattern, by either using a backslash (
\!), or otherwise making it not the first character of the regex (
/[!], for example).
The other way is to use
$ man find | grep ! with `-', or the argument `(' or `!'. That argument and any following ! expr True if expr is false. This character will also usually need Same as ! expr, but not POSIX compliant. The POSIX standard specifies parentheses `(', `)', negation `!' and the find /sbin /usr/sbin -executable \! -readable -print find . -perm -444 -perm /222 ! -perm /111 find . -perm -a+r -perm /a+w ! -perm /a+x -perm /222 or -perm /a+w) but are not executable for anybody ( ! -perm /111 and ! -perm /a+x respectively). find . -name .snapshot -prune -o \( \! -name *~ -print0 \)|