1 files changed, 44 insertions, 0 deletions
diff --git a/login-utils/mesg.c b/login-utils/mesg.c
new file mode 100644
index 000000000..07c5fad1f
--- /dev/null
+++ b/login-utils/mesg.c
@@ -0,0 +1,44 @@
+/*
+ * mesg.c	The "mesg" utility. Gives / restrict access to
+ *		your terminal by others.
+ *
+ * Usage:	mesg [y|n].
+ *		Without arguments prints out the current settings.
+ */
+#include <stdio.h>
+#include <sys/stat.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <unistd.h>
+
+char *Version = "@(#) mesg 1.0 08-12-92 MvS";
+
+int main(int argc, char **argv)
+{
+  struct stat st;
+
+  if (!isatty(0)) {
+	/* Or should we look in /etc/utmp? */
+	fprintf(stderr, "stdin: is not a tty");
+	return(1);
+  }
+
+  if (fstat(0, &st) < 0) {
+	perror("fstat");
+	return(1);
+  }
+  if (argc < 2) {
+	printf("Is %s\n", ((st.st_mode & 022) == 022) ? "y" : "n");
+	return(0);
+  }
+  if (argc > 2 || (argv[1][0] != 'y' && argv[1][0] != 'n')) {
+	fprintf(stderr, "Usage: mesg [y|n]\n");
+	return(1);
+  }
+  if (argv[1][0] == 'y')
+	st.st_mode |= 022;
+  else
+	st.st_mode &= ~022;
+  fchmod(0, st.st_mode);
+  return(0);
+}