Element | Effect(s) if set | |
icase | Specifies that matching of regular expressions against a character
container sequence shall be performed without regard to case. | |
nosubs | Specifies that no sub-expressions shall be considered to be marked, so that
when a regular expression is matched against a
character container sequence, no sub-expression matches shall be
stored in the supplied match_results object. | |
optimize | ||
collate | ||
ECMAScript | Specifies that the grammar recognized by the regular expression engine
shall be that used by ECMAScript in ECMA-262, as modified in [re.grammar]. | |
basic | Specifies that the grammar recognized by the regular expression engine
shall be that used by basic regular expressions in POSIX. See also: POSIX, Base Definitions and Headers, Section 9.3 | |
extended | Specifies that the grammar recognized by the regular expression engine
shall be that used by extended regular expressions in POSIX. See also: POSIX, Base Definitions and Headers, Section 9.4 | |
awk | Specifies that the grammar recognized by the regular expression engine
shall be that used by the utility awk in POSIX. | |
grep | Specifies that the grammar recognized by the regular expression engine
shall be that used by the utility grep in POSIX. | |
egrep | Specifies that the grammar recognized by the regular expression engine
shall be that used by the utility grep when given the -E
option in POSIX. | |
multiline | Specifies that ^ shall match the beginning of a line and
$ shall match the end of a line,
if the ECMAScript engine is selected. |