Node:Flags for POSIX Regexps, Next:Matching POSIX Regexps, Previous:POSIX Regexp Compilation, Up:Regular Expressions
These are the bit flags that you can use in the cflags operand when
compiling a regular expression with regcomp.
REG_EXTENDED
REG_ICASE
REG_NOSUB
REG_NEWLINE
$ can match before the newline and ^ can
match after. Also, don't permit . to match a newline, and don't
permit [^...] to match a newline.
Otherwise, newline acts like any other ordinary character.