fix fclose of permanent (stdin/out/err) streams

[musl] / src / stdio / ftell.c

diff --git a/src/stdio/ftell.c b/src/stdio/ftell.c
index 3904a1d..bb62897 100644 (file)
--- a/src/stdio/ftell.c
+++ b/src/stdio/ftell.c
@@ -1,8 +1,12 @@
 #include "stdio_impl.h"
+#include <limits.h>
+#include <errno.h>
 
 off_t __ftello_unlocked(FILE *f)
 {
-       off_t pos = f->seek(f, 0, SEEK_CUR);
+       off_t pos = f->seek(f, 0,
+               (f->flags & F_APP) && f->wpos > f->wbase
+               ? SEEK_END : SEEK_CUR);
        if (pos < 0) return pos;
 
        /* Adjust for data in buffer. */