Prefer "kill -INT" to killing with a number

* m4/pthread_sigmask.m4 (gl_FUNC_PTHREAD_SIGMASK):
* tests/test-login_tty.c (main):
* tests/test-pthread_sigmask1.c (main):
* tests/test-sigprocmask.c (main):
Prefer "kill -INT" to "kill -N" where N is SIGINT’s value.
Don’t assume pid_t fits in int.

1 files changed, 5 insertions, 2 deletions

diff --git a/m4/pthread_sigmask.m4 b/m4/pthread_sigmask.m4
index 0aa8c53f9e..8282a371e4 100644
--- a/m4/pthread_sigmask.m4
+++ b/m4/pthread_sigmask.m4
@@ -215,6 +215,7 @@ int main ()
            LIBS="$LIBS $LIBMULTITHREAD"])
         AC_RUN_IFELSE(
           [AC_LANG_SOURCE([[
+#include <limits.h>
 #include <pthread.h>
 #include <signal.h>
 #include <stdio.h>
@@ -230,14 +231,16 @@ sigint_handler (int sig)
 int main ()
 {
   sigset_t set;
-  int pid = getpid ();
+  pid_t pid = getpid ();
   char command[80];
+  if (LONG_MAX < pid)
+    return 6;
   signal (SIGINT, sigint_handler);
   sigemptyset (&set);
   sigaddset (&set, SIGINT);
   if (!(pthread_sigmask (SIG_BLOCK, &set, NULL) == 0))
     return 1;
-  sprintf (command, "sh -c 'sleep 1; kill -%d %d' &", SIGINT, pid);
+  sprintf (command, "sh -c 'sleep 1; kill -INT %ld' &", (long) pid);
   if (!(system (command) == 0))
     return 2;
   sleep (2);