Date: Sat, 21 Apr 2001 13:19:57 -0700 From: Dima Dorfman <dima@unixfreak.org> To: Jordan Hubbard <jkh@osd.bsdi.com> Cc: freebsd-current@FreeBSD.ORG, olli@secnetix.de Subject: Re: cp -d dir patch for review (or 'xargs'?) Message-ID: <20010421201957.D12FD3E09@bazooka.unixfreak.org> In-Reply-To: <20010421130719H.jkh@osd.bsdi.com>; from jkh@osd.bsdi.com on "Sat, 21 Apr 2001 13:07:19 -0700"
next in thread | previous in thread | raw e-mail | index | archive | help
Jordan Hubbard <jkh@osd.bsdi.com> writes:
> > And to come back on topic: Portable scripts also should
> > _not_ assume that there are no limits on the length of
> > shell commands. On the other hand, portable scripts can
> > legitimately assume that xargs supports -i and -I, which
> > ours doesn't.
>
> Agreed on both counts. I guess we should fix that.
I don't have a copy of SuSv2 or anything else that defines -I and -i,
but from what I can gather, -i is the same as "-I {}" and -I allows
things like this:
dima@spike% ./xargs -I [] echo CMD LINE [] ARGS < test
CMD LINE this is the contents of the test file ARGS
dima@spike% ./xargs -I [] echo CMD [] LINE ARGS < test
CMD this is the contents of the test file LINE ARGS
dima@spike% ./xargs -I [] echo [] CMD LINE ARGS < test
this is the contents of the test file CMD LINE ARGS
Does that mean everyone is blind and missed my arrogant cross-post of
the amazingly short patch to do this, or are we just interested in
discussing it and not testing the implementation? ;-)
FWIW, I'm not sure the patch is entirely correct; xargs' processing of
this stuff looks like black magic. It works, but I'm not sure if I
failed to cater to some other weird assumptions it makes. This is why
it'd help if someone would at least look at it.
Thanks,
Dima Dorfman
dima@unixfreak.org
Index: xargs.c
===================================================================
RCS file: /st/src/FreeBSD/src/usr.bin/xargs/xargs.c,v
retrieving revision 1.9
diff -u -r1.9 xargs.c
--- xargs.c 1999/08/28 01:07:50 1.9
+++ xargs.c 2001/04/21 20:15:27
@@ -73,6 +73,8 @@
int cnt, indouble, insingle, nargs, nflag, nline, xflag, wasquoted;
char **av, *argp, **ep = env;
long arg_max;
+ int apargs = 0;
+ char **avv, *replstr = NULL;
/*
* POSIX.2 limits the exec line length to ARG_MAX - 2K. Running that
@@ -96,8 +98,14 @@
nline -= strlen(*ep++) + 1 + sizeof(*ep);
}
nflag = xflag = wasquoted = 0;
- while ((ch = getopt(argc, argv, "0n:s:tx")) != -1)
+ while ((ch = getopt(argc, argv, "0I:in:s:tx")) != -1)
switch(ch) {
+ case 'I':
+ replstr = optarg;
+ break;
+ case 'i':
+ replstr = "{}";
+ break;
case 'n':
nflag = 1;
if ((nargs = atoi(optarg)) <= 0)
@@ -144,6 +152,13 @@
else {
cnt = 0;
do {
+ if (replstr && strcmp(*argv, replstr) == 0) {
+ apargs = 1;
+ *argv++;
+ for (avv = argv; *avv; *avv++)
+ cnt += strlen(*avv) + 1;
+ break;
+ }
cnt += strlen(*bxp++ = *argv) + 1;
} while (*++argv);
}
@@ -211,6 +226,8 @@
if (xp == exp || p > ebp || ch == EOF) {
if (xflag && xp != exp && p > ebp)
errx(1, "insufficient space for arguments");
+ for (avv = argv; apargs && *avv; *avv++)
+ strlen(*xp++ = *avv) + 1;
*xp = NULL;
run(av);
if (ch == EOF)
@@ -253,6 +270,8 @@
if (xflag)
errx(1, "insufficient space for arguments");
+ for (avv = argv; apargs && *avv; *avv++)
+ strlen(*xp++ = *avv) + 1;
*xp = NULL;
run(av);
xp = bxp;
To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-current" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20010421201957.D12FD3E09>