fseek.c:

Resulting fseek() offset must fit in long, required by POSIX (pointed by bde),
so add LONG_MAX and final tests for it.

rewind.c:
1) add missing __sinit() as in fseek() it pretends to be.
2) use clearerr_unlocked() since we already lock stream before _fseeko()
3) don't zero errno at the end, it explicitely required by POSIX as the
only one method to test rewind() error condition.
4) don't clearerr() if error happens in _fseeko()

1 files changed, 7 insertions, 3 deletions

diff --git a/lib/libc/stdio/rewind.c b/lib/libc/stdio/rewind.c
index c4de2c1..af9232a 100644
--- a/lib/libc/stdio/rewind.c
+++ b/lib/libc/stdio/rewind.c
@@ -52,9 +52,13 @@ static const char rcsid[] =
 void
 rewind(FILE *fp)
 {
+	/* make sure stdio is set up */
+	if (!__sdidinit)
+		__sinit();
+
 	FLOCKFILE(fp);
-	(void) _fseeko(fp, (off_t)0, SEEK_SET);
-	clearerr(fp);
+	if (_fseeko(fp, (off_t)0, SEEK_SET, 1) == 0)
+		clearerr_unlocked(fp);
 	FUNLOCKFILE(fp);
-	errno = 0;	/* not required, but seems reasonable */
+	/* errno required by POSIX to sense error, don't zero it here */
 }