On Thu, 30 Apr 2015 05:58:57 -0600, "Todd C. Miller" wrote:
> GNU grep warns in this case before reading from stdin which seems reasonable.
> % grep -R foo
> grep: warning: recursive search of stdin
> ...
>
> I'd rather add a warning than change the behavior.
Trivial diff to add the warning.
- todd
Index: usr.bin/grep/grep.c
===================================================================
RCS file: /cvs/src/usr.bin/grep/grep.c,v
retrieving revision 1.50
diff -u -p -u -r1.50 grep.c
--- usr.bin/grep/grep.c 16 Mar 2015 13:27:59 -0000 1.50
+++ usr.bin/grep/grep.c 30 Apr 2015 12:01:32 -0000
@@ -444,6 +444,8 @@ main(int argc, char *argv[])
++argv;
}
+ if (Rflag && argc == 0)
+ warnx("warning: recursive search of stdin");
if (Eflag)
cflags |= REG_EXTENDED;
if (Fflag)
