Further improvements in system return value and doc.

1 files changed, 15 insertions, 8 deletions

diff --git a/builtin.c b/builtin.c
index da664e3a..c3a3bb22 100644
--- a/builtin.c
+++ b/builtin.c
@@ -2064,6 +2064,7 @@ do_system(int nargs)
 	AWKNUM ret = 0;		/* floating point on purpose, compat Unix awk */
 	char *cmd;
 	char save;
+	int status;
 
 	if (do_sandbox)
 		fatal(_("'system' function not allowed in sandbox mode"));
@@ -2080,7 +2081,7 @@ do_system(int nargs)
 		cmd[tmp->stlen] = '\0';
 
 		os_restore_mode(fileno(stdin));
-		ret = system(cmd);
+		status = system(cmd);
 		/*
 		 * 3/2016. What to do with ret? It's never simple.
 		 * POSIX says to use the full return value. BWK awk
@@ -2088,17 +2089,23 @@ do_system(int nargs)
 		 * exit status but gives a weird result for death-by-signal.
 		 * So we compromise as follows:
 		 */
-		if (ret != -1) {
+		ret = status;
+		if (status != -1) {
 			if (do_posix)
 				;	/* leave it alone, full 16 bits */
 			else if (do_traditional)
-				ret /= 256.0;
-			else if (WIFEXITED(ret))
-				ret = WEXITSTATUS(ret);	/* normal exit */
-			else if (WIFSIGNALED(ret))
+				ret = (status / 256.0);
+			else if (WIFEXITED(status))
+				ret = WEXITSTATUS(status); /* normal exit */
+			else if (WIFSIGNALED(status)) {
+				bool coredumped = false;
+#ifdef WCOREDUMP
+				coredumped = WCOREDUMP(status);
+#endif
 				/* use 256 since exit values are 8 bits */
-				ret = WTERMSIG(ret) + 256;
-			else
+				ret = WTERMSIG(status) +
+					(coredumped ? 512 : 256);
+			} else
 				ret = 0;	/* shouldn't get here */
 		}
 		if ((BINMODE & BINMODE_INPUT) != 0)