Use /dev/tty instead of stdout to get terminal size

diff --git a/center.c b/center.c
index 1b030849b24db11da62552b6f53b8de887b10268..a08e9e7349ce1082fdd784ae7ae3e21a9fc6723f 100644 (file)
--- a/center.c
+++ b/center.c
@@ -1,12 +1,15 @@
 #define _POSIX_C_SOURCE 200809L
 #define _XOPEN_SOURCE
+#include <fcntl.h>
+#include <locale.h>
 #include <stdio.h>
-#include <wchar.h>
 #include <stdlib.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
 #include <termios.h>
 #include <unistd.h>
-#include <sys/ioctl.h>
-#include <locale.h>
+#include <wchar.h>
 
 #define ERR(str) { perror(str); err = EXIT_FAILURE; goto end; }
 
@@ -22,9 +25,15 @@ int main()
        ssize_t len;
        int err = EXIT_SUCCESS;
 
+       int tty_fd = open("/dev/tty", O_RDWR);
+       if (tty_fd < 0) {
+               perror("open");
+               return EXIT_FAILURE;
+       }
+
        while ((len = getline(&buf, &siz, stdin)) > 0) {
                struct winsize ws;
-               if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws) < 0) ERR("ioctl")
+               if (ioctl(tty_fd, TIOCGWINSZ, &ws) < 0) ERR("ioctl")
 
                int term_width = ws.ws_col;
 
@@ -61,6 +70,8 @@ int main()
        }
 
        end:
+       close(tty_fd);
+
        if (buf)
                free(buf);