streams: use Boolean return value for stdio_fseek.

* stream.c (stdio_seek): Handle new-style Boolean return from
stdio_fseek.

* sysif.c (stdio_fseek): Return an int indication that is 1
for success, 0 for failure. There was a mistaken assumption
here that fseeko returns the file offset, and the return value
in the fseek case was mistakenly harmonized, using a wasteful
call to stdio_ftell. The only call to this function relies
only on a Boolean success/fail indication.

* sysif.h (stdio_fseek): Declaration updated.

1 files changed, 3 insertions, 4 deletions

diff --git a/sysif.c b/sysif.c
index ae469b07..04ed6ea5 100644
--- a/sysif.c
+++ b/sysif.c
@@ -1364,14 +1364,13 @@ val stdio_ftell(FILE *f)
 #endif
 }
 
-val stdio_fseek(FILE *f, val off, int whence)
+int stdio_fseek(FILE *f, val off, int whence)
 {
   val self = lit("seek-stream");
 #if HAVE_FSEEKO
-  return num_off_t(fseeko(f, off_t_num(off, self), whence));
+  return fseeko(f, off_t_num(off, self), whence) == 0;
 #else
-  int ret = fseek(f, c_long(off, self), whence);
-  return (ret == -1) ? num_fast(ret) : stdio_ftell(f);
+  return fseek(f, c_long(off, self), whence) == 0;
 #endif
 }