shell - How can I check the version of sed in OS X?

Question

I know if sed is GNU version, version check can be done like

$ sed --version

But this doesn't work in OS X. How can I do that?

Answer 1

This probably isn't the answer you're looking for, but you can't. Mac OS X sed has no option to show the version number.

There is not even a version number in the binary:

$ strings $(which sed)
$FreeBSD: src/usr.bin/sed/compile.c,v 1.28 2005/08/04 10:05:11 dds Exp $
$FreeBSD: src/usr.bin/sed/main.c,v 1.36 2005/05/10 13:40:50 glebius Exp $
$FreeBSD: src/usr.bin/sed/misc.c,v 1.10 2004/08/09 15:29:41 dds Exp $
$FreeBSD: src/usr.bin/sed/process.c,v 1.39 2005/04/09 14:31:41 stefanf Exp $
@(#)PROGRAM:sed  PROJECT:text_cmds-88
malloc
%lu: %s: unexpected EOF (pending }'s)
0123456789/$
%lu: %s: command expected
%lu: %s: invalid command code %c
%lu: %s: command %c expects up to %d address(es), found %d
%lu: %s: unexpected }
%lu: %s: extra characters at the end of %c command
%lu: %s: command %c expects  followed by text
%lu: %s: extra characters after  at the end of %c command
%lu: %s: filename expected
w command
read command
branch
label
%lu: %s: empty label
%lu: %s: substitute pattern can not be delimited by newline or backslash
%lu: %s: unterminated substitute pattern
%lu: %s: extra text at the end of a transform command
%lu: %s: unterminated regular expression
%lu: %s: expected context address
realloc
%lu: %s: whitespace after %s
%lu: %s: duplicate label '%s'
%lu: %s: RE error: %s
%lu: %s:  can not be used as a string delimiter
%lu: %s: newline can not be used as a string delimiter
%lu: %s: unbalanced brackets ([])
bin/sed
Unix2003
123456789
%lu: %s: \%c not defined in the RE
%lu: %s: unescaped newline inside substitute pattern
%lu: %s: unterminated substitute in regular expression
%lu: %s: more than one number or 'g' in substitute flags
%lu: %s: overflow in the 'N' substitute flag
%lu: %s: no wfile specified
%lu: %s: bad flag in substitute command: '%c'
%lu: %s: transform pattern can not be delimited by newline or backslash
%lu: %s: unterminated transform source string
%lu: %s: unterminated transform target string
%lu: %s: transform strings are not the same length
%lu: %s: undefined label '%s'
%lu: %s: unused label '%s'
Eae:f:i:ln
setlinebuf() failed
stdout
"%s"
 ..."
-i may not be used with stdin
stdin
rename()
%s: %s %s
in-place editing only
works for regular files
%s: name too long
%s/.!%ld!%s
%s: %s
usage: sed script [-Ealn] [-i extension] [file ...]
       sed [-Ealn] [-i extension] [-e script] ... [-f script_file] ... [file ...]
first RE may not be empty
RE error: %s
%lu: %s: \%d not defined in the RE
COLUMNS
abfrtv
\%03o