+ busybox --install [-s]

is almost good to go.  Here is my work in progress.

+ Look at the FIXME in busybox.c
  to see what I need.  The actual (sym)linking is disabled
  for now, although I'm sure it works ;)
  (Am I going to have to dig through /proc to find
  out where the currently running busybox is sitting?)

+ I put an #ifdef BB_FEATURE_INSTALLER around
  the new bits of code in busybox.c, and I have a
  #define BB_FEATURE_INSTALLER in busybox.def.h
  towards the bottom.

applets/busybox.c

@@ -358,6 +358,60 @@ const struct BB_applet applets[] = {
 };
 
 
+#ifdef BB_FEATURE_INSTALLER
+/* 
+ * directory table
+ *      this should be consistent w/ the enum, internal.h::Location,
+ *      or else...
+ */
+static char* install_dir[] = {
+    "/",
+    "/bin",
+    "/sbin",
+    "/usr/bin",
+    "/usr/sbin",
+	NULL
+};
+
+/* abstract link() */
+typedef int (*__link_f)(const char *, const char *);
+
+/* create (sym)links for each applet */
+int install_links(const char *busybox, int use_symbolic_links)
+{
+    __link_f Link = link;
+
+    char	command[256];
+	int		i;
+	int		rc = 0;
+
+	if (use_symbolic_links) Link = symlink;
+
+    for (i = 0; applets[i].name != NULL; i++) {
+        sprintf (
+			command, 
+			"%s/%s", 
+			install_dir[applets[i].location], 
+			applets[i].name
+		);
+#if 0
+        rc |= Link(busybox, command);
+#else
+        puts(command);
+#endif
+		if (rc) {
+			fprintf(stderr,"busybox : %s : %s\n", command, strerror(errno));
+			break;
+		}
+    }
+	return rc;
+}
+
+#if 0
+int uninstall_links() ?
+#endif
+#endif /* BB_FEATURE_INSTALLER */
+
 
 int main(int argc, char **argv)
 {
@@ -365,6 +419,26 @@ int main(int argc, char **argv)
 	char				*name;
 	const struct BB_applet	*a		= applets;
 
+#ifdef BB_FEATURE_INSTALLER	
+	if (argc > 1 && (strcmp(argv[1], "--install") == 0)) {
+		int use_symbolic_links = 0;
+
+		/* to use symlinks, or to not use symlinks... */
+		if (argc > 2) {
+			if ((strcmp(argv[2], "-s") == 0)) { 
+				use_symbolic_links = 1; 
+			}
+		}
+		/* 
+		 * FIXME : 
+		 * I need a clever unix trick that'll tell
+		 * me where to find the currently running
+		 * busybox binary
+		 */
+		return install_links("/bin/busybox", use_symbolic_links);
+	}
+#endif /* BB_FEATURE_INSTALLER */
+
 	for (s = name = argv[0]; *s != '\0';) {
 		if (*s++ == '/')
 			name = s;

busybox.c

@@ -358,6 +358,60 @@ const struct BB_applet applets[] = {
 };
 
 
+#ifdef BB_FEATURE_INSTALLER
+/* 
+ * directory table
+ *      this should be consistent w/ the enum, internal.h::Location,
+ *      or else...
+ */
+static char* install_dir[] = {
+    "/",
+    "/bin",
+    "/sbin",
+    "/usr/bin",
+    "/usr/sbin",
+	NULL
+};
+
+/* abstract link() */
+typedef int (*__link_f)(const char *, const char *);
+
+/* create (sym)links for each applet */
+int install_links(const char *busybox, int use_symbolic_links)
+{
+    __link_f Link = link;
+
+    char	command[256];
+	int		i;
+	int		rc = 0;
+
+	if (use_symbolic_links) Link = symlink;
+
+    for (i = 0; applets[i].name != NULL; i++) {
+        sprintf (
+			command, 
+			"%s/%s", 
+			install_dir[applets[i].location], 
+			applets[i].name
+		);
+#if 0
+        rc |= Link(busybox, command);
+#else
+        puts(command);
+#endif
+		if (rc) {
+			fprintf(stderr,"busybox : %s : %s\n", command, strerror(errno));
+			break;
+		}
+    }
+	return rc;
+}
+
+#if 0
+int uninstall_links() ?
+#endif
+#endif /* BB_FEATURE_INSTALLER */
+
 
 int main(int argc, char **argv)
 {
@@ -365,6 +419,26 @@ int main(int argc, char **argv)
 	char				*name;
 	const struct BB_applet	*a		= applets;
 
+#ifdef BB_FEATURE_INSTALLER	
+	if (argc > 1 && (strcmp(argv[1], "--install") == 0)) {
+		int use_symbolic_links = 0;
+
+		/* to use symlinks, or to not use symlinks... */
+		if (argc > 2) {
+			if ((strcmp(argv[2], "-s") == 0)) { 
+				use_symbolic_links = 1; 
+			}
+		}
+		/* 
+		 * FIXME : 
+		 * I need a clever unix trick that'll tell
+		 * me where to find the currently running
+		 * busybox binary
+		 */
+		return install_links("/bin/busybox", use_symbolic_links);
+	}
+#endif /* BB_FEATURE_INSTALLER */
+
 	for (s = name = argv[0]; *s != '\0';) {
 		if (*s++ == '/')
 			name = s;

busybox.def.h

@@ -230,6 +230,11 @@
 //#define BB_FEATURE_INSMOD_VERSION_CHECKING
 //
 //
+// Enable busybox --install [-s]
+// to create links (or symlinks) for all the commands that are 
+// compiled into the binary.
+#define BB_FEATURE_INSTALLER
+//
 // End of Features List
 //
 //