From fc6f690727aac2b5c9bd368f9b13188fb0ba36a7 Mon Sep 17 00:00:00 2001 From: user Date: Thu, 16 Jul 2026 13:07:28 +0200 Subject: fs: reject open()/read() on a directory (EISDIR) open() now checks the target's inode type: opening a directory as a file returns $FE (EISDIR) instead of a valid fd, so 'cat docs' no longer streams the raw directory block as bytes. cat reports 'is a directory'; wc/head/save treat any invalid fd (>3) as an open failure. (ls is unaffected - it uses the structural opendir/list path, not open/getb.) --- c/save.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'c/save.c') diff --git a/c/save.c b/c/save.c index dd2b8cd..1755fea 100644 --- a/c/save.c +++ b/c/save.c @@ -7,7 +7,7 @@ void main(void) { char c; if (argc < 1) { puts("usage: save "); nl(); return; } fd = open(argv[0], O_WRITE); - if (fd == NOFD) { puts("save: cannot create"); nl(); return; } + if (fd > 3) { puts("save: cannot create"); nl(); return; } for (;;) { c = readc(); if (c == EOF) break; -- cgit v1.3.1-sl0p