New file to implement signal(2).

c/src/exec/posix/src/signal_2.c

@@ -0,0 +1,50 @@
+/*
+ *  signal(2) - Install signal handler
+ *
+ *  COPYRIGHT (c) 1989-1998.
+ *  On-Line Applications Research Corporation (OAR).
+ *  Copyright assigned to U.S. Government, 1994.
+ *
+ *  The license and distribution terms for this file may be
+ *  found in the file LICENSE in this distribution or at
+ *  http://www.OARcorp.com/rtems/license.html.
+ *
+ *  $Id$
+ */
+
+
+#include <signal.h>
+#include <errno.h>
+
+typedef void (*sighandler_t)(int);
+
+sighandler_t signal(
+  int           signum,
+  sighandler_t  handler
+)
+{
+  struct sigaction s;
+  struct sigaction old;
+
+  s.sa_handler = handler ;
+  sigemptyset(&s.sa_mask);
+
+  /*
+   *  Depending on which system we want to behave like, one of
+   *  the following versions should be chosen.
+   */
+
+/* #define signal_like_linux */
+
+#if defined(signal_like_linux)
+  s.sa_flags   = SA_RESTART | SA_INTERRUPT | SA_NOMASK;
+  s.sa_restorer= NULL ;
+#elif defined(signal_like_SVR4)
+  s.sa_flags   = SA_RESTART;
+#else
+  s.sa_flags   = 0;
+#endif
+
+  sigaction( signum, &s, &old );
+  return (sighandler_t) old.sa_handler;
+}