added a comment to spawn

[dwm.git] / util.c

diff --git a/util.c b/util.c
index 4cc748f..91df00b 100644 (file)
--- a/util.c
+++ b/util.c
@@ -9,14 +9,6 @@
 #include <sys/wait.h>
 #include <unistd.h>
 
-/* static */
-
-static void
-bad_malloc(unsigned int size)
-{
-       eprint("fatal: could not malloc() %u bytes\n", size);
-}
-
 /* extern */
 
 void *
@@ -25,7 +17,7 @@ emallocz(unsigned int size)
        void *res = calloc(1, size);
 
        if(!res)
-               bad_malloc(size);
+               eprint("fatal: could not malloc() %u bytes\n", size);
        return res;
 }
 
@@ -40,6 +32,15 @@ eprint(const char *errstr, ...)
        exit(EXIT_FAILURE);
 }
 
+void *
+erealloc(void *ptr, unsigned int size)
+{
+       void *res = realloc(ptr, size);
+       if(!res)
+               eprint("fatal: could not malloc() %u bytes\n", size);
+       return res;
+}
+
 void
 spawn(Arg *arg)
 {
@@ -50,12 +51,13 @@ spawn(Arg *arg)
 
        if(!arg->cmd)
                return;
+       /* the double-fork construct avoids zombie processes */
        if(fork() == 0) {
                if(fork() == 0) {
                        if(dpy)
                                close(ConnectionNumber(dpy));
                        setsid();
-                       execl(shell, shell, "-c", arg->cmd, NULL);
+                       execl(shell, shell, "-c", arg->cmd, (char *)NULL);
                        fprintf(stderr, "dwm: execl '%s -c %s'", shell, arg->cmd);
                        perror(" failed");
                }