utils

commit: e1aa97f70e6005d675b741c59063a602141378ee
parent ec98fcc8ee03157d9da25886729904744a92b1fe
Author: Haelwenn (lanodan) Monnier <contact@hacktivis.me>
Date:   Tue,  1 Mar 2022 18:15:31 +0100

bin/tty: Reduce syscalls

Diffstat:
M
bin/tty.c
19
+++++++++++--------

1 file changed, 11 insertions(+), 8 deletions(-)
diff --git a/bin/tty.c b/bin/tty.c
@@ -2,23 +2,26 @@
 // Copyright 2017-2022 Haelwenn (lanodan) Monnier <contact+utils@hacktivis.me>
 // SPDX-License-Identifier: GPL-2.0-only OR GPL-3.0-only
 
+#include <errno.h>  // errno
 #include <stdio.h>  // puts()
 #include <unistd.h> // ttyname(), isatty()
 
 int
 main(void)
 {
-	if(!isatty(STDIN_FILENO))
-	{
-		puts("not a tty");
-		return 1;
-	}
-
 	char *name = ttyname(STDIN_FILENO);
 	if(!name)
 	{
-		perror("ttyname");
-		return 2;
+		if(errno == ENOTTY)
+		{
+			puts("not a tty");
+			return 1;
+		}
+		else
+		{
+			perror("ttyname");
+			return 2;
+		}
 	}
 
 	puts(name);