> On Apr 4, 2017, at 4:46 PM, Nicholas Marriott <nicholas.marri...@gmail.com>
> wrote:
>
> readlink is explicitly documented to silently exit 1 if run without -f,
> and GNU readlink behaves the same way. I doubt that should change.
Yeah, I saw that. I (incorrectly, I guess?) interpreted it to mean
"does not print anything on the standard output."
My think is -- and maybe I'm being nitpicky, but -- the documentation
says:
> If the -f option is not specified and readlink is invoked with an
> argument other than the pathname of a symbolic link, it exits with
> a nonzero exit code without printing anything.
In the current code, however, you could have insufficient permissions
for a part of the path (EPERM), or an I/O failure (EIO), but otherwise
specify a valid symbolic link, and still get the described behavior,
which seems wrong to me.
If the documented "say nothing and exit 1" behavior when the target
is not a symbolic link is sacred, then maybe this snippet is better:
if (fflag) {
if (realpath(argv[0], buf) == NULL)
err(1, "%s", argv[0]);
} else {
- if ((n = readlink(argv[0], buf, sizeof buf-1)) < 0)
- exit(1);
+ if ((n = readlink(argv[0], buf, sizeof(buf) - 1)) == -1) {
+ if (errno != EINVAL)
+ warn("%s", argv[0]);
+ return 1;
+ }
buf[n] = '\0';
}
That way you still say nothing if the issue is, in fact, that your target
isn't a symbolic link, but you point out any other errors.
--
Scott Cheloha
