diff options
| author | steve <steve@FreeBSD.org> | 1998-02-14 18:26:29 +0000 |
|---|---|---|
| committer | steve <steve@FreeBSD.org> | 1998-02-14 18:26:29 +0000 |
| commit | 623d77caec9639b94505b72f7c2cbd21a97e3812 (patch) | |
| tree | 4254a3466b903a491268394b42971e626944a00f /lib | |
| parent | ee159ceedeb5d55374844cf9cc3e975fb301db88 (diff) | |
| download | FreeBSD-src-623d77caec9639b94505b72f7c2cbd21a97e3812.zip FreeBSD-src-623d77caec9639b94505b72f7c2cbd21a97e3812.tar.gz | |
Note that '+' and '?' are not special characters in basic REs but they
can be simulated using bounds.
PR: 5708
Submitted by: Oliver Fromme <oliver.fromme@heim3.tu-clausthal.de>
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/libc/regex/re_format.7 | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/lib/libc/regex/re_format.7 b/lib/libc/regex/re_format.7 index db2f634..d663f11 100644 --- a/lib/libc/regex/re_format.7 +++ b/lib/libc/regex/re_format.7 @@ -222,8 +222,11 @@ as an implementation can refuse to accept such REs and remain POSIX-compliant. .PP Obsolete (``basic'') regular expressions differ in several respects. -`|', `+', and `?' are ordinary characters and there is no equivalent -for their functionality. +`|' is an ordinary character and there is no equivalent +for its functionality. +`+' and `?' are ordinary characters, and their functionality +can be expressed using bounds (\&{1,\&} or \&{0,1\&} respectively). +Also note that `x+' in modern REs is equivalent to `xx*'. The delimiters for bounds are `\e{' and `\e}', with `{' and `}' by themselves ordinary characters. The parentheses for nested subexpressions are `\e(' and `\e)', |
