z/OS V1R9.0 UNIX System Services Command ... - Christian Grothoff

grep
Options
egrep works in a similar way, but uses extended regular expression matching. (For
information about regular expression matching, see Appendix C.) If you include
special characters in patterns typed on the command line, escape them by
enclosing them in apostrophes to prevent inadvertent misinterpretation by the shell
or command interpreter. To match a character that is special to egrep, put a
backslash (\) in front of the character. It is usually simpler to use fgrep when you
don’t need special pattern matching.
grep is a combination of fgrep and egrep. If you do not specify either –E or –F,
grep behaves like egrep, but matches basic regular expressions instead of
extended ones. You can specify a pattern to search with either the –e or –f option.
If you do not specify either option, grep (or egrep or fgrep) takes the first
non-option argument as the pattern for which to search. If grep finds a line that
matches a pattern, it displays the entire line. If you specify multiple input files, the
name of the current file precedes each output line.
grep accepts all the following options while egrep and fgrep accept all but the –E
and –F options.
–b Precedes each matched line with its file block number.
–c Displays only a count of the number of matched lines and not the lines
themselves.
–E Matches using extended regular expressions (causes grep to behave like
egrep).
–e pattern
Specifies one or more patterns separated by newlines for which grep is to
search.
You can indicate each pattern with a separate –e option character, or with
newlines within pattern. For example, the following two commands are
equivalent:
grep –e pattern_one –epattern_two file
grep –e 'pattern_one
pattern_two' file
–F Matches using fixed strings (causes grep to behave like fgrep).
–f patternfile
Reads one or more patterns from patternfile. Patterns in patternfile are
separated by newlines.
–i Ignores the case of the strings being matched.
–l Lists only the filenames that contain the matching lines.
–n Precedes each matched line with its fileline number.
–q Suppresses output and returns the appropriate return code.
–s Suppresses the display of any error messages for nonexistent or
unreadable files.
–v Complements the sense of the match—that is, displays all lines not
matching a pattern.
–x Requires a string to match an entire line.
304 z/OS V1R9.0 UNIX System Services Command Reference