Alter how tmux handles the working directory to internally use file

descriptors rather than strings.

- Each session still has a current working directory.

- New sessions still get their working directory from the client that
  created them or its attached session if any.

- New windows are created by default in the session working directory.

- The -c flag to new, neww, splitw allows the working directory to be
  overridden.

- The -c flag to attach let's the session working directory be changed.

- The default-path option has been removed.

To get the equivalent to default-path '.', do:

        bind c neww -c $PWD

To get the equivalent of default-path '~', do:

        bind c neww -c ~

This also changes the client identify protocol to be a set of messages rather
than one as well as some other changes that should make it easier to make
backwards-compatible protocol changes in future.

1 files changed, 8 insertions, 8 deletions

diff --git a/window.c b/window.c
index 0ea70688..83e14db6 100644
--- a/window.c
+++ b/window.c
@@ -309,7 +309,7 @@ window_create1(u_int sx, u_int sy)
 
 struct window *
 window_create(const char *name, const char *cmd, const char *shell,
-    const char *cwd, struct environ *env, struct termios *tio,
+    int cwd, struct environ *env, struct termios *tio,
     u_int sx, u_int sy, u_int hlimit, char **cause)
 {
 	struct window		*w;
@@ -675,7 +675,7 @@ window_pane_create(struct window *w, u_int sx, u_int sy, u_int hlimit)
 
 	wp->cmd = NULL;
 	wp->shell = NULL;
-	wp->cwd = NULL;
+	wp->cwd = -1;
 
 	wp->fd = -1;
 	wp->event = NULL;
@@ -730,7 +730,7 @@ window_pane_destroy(struct window_pane *wp)
 
 	RB_REMOVE(window_pane_tree, &all_window_panes, wp);
 
-	free(wp->cwd);
+	close(wp->cwd);
 	free(wp->shell);
 	free(wp->cmd);
 	free(wp);
@@ -738,7 +738,7 @@ window_pane_destroy(struct window_pane *wp)
 
 int
 window_pane_spawn(struct window_pane *wp, const char *cmd, const char *shell,
-    const char *cwd, struct environ *env, struct termios *tio, char **cause)
+    int cwd, struct environ *env, struct termios *tio, char **cause)
 {
 	struct winsize	 ws;
 	char		*argv0, paneid[16];
@@ -757,9 +757,9 @@ window_pane_spawn(struct window_pane *wp, const char *cmd, const char *shell,
 		free(wp->shell);
 		wp->shell = xstrdup(shell);
 	}
-	if (cwd != NULL) {
-		free(wp->cwd);
-		wp->cwd = xstrdup(cwd);
+	if (cwd != -1) {
+		close(wp->cwd);
+		wp->cwd = dup(cwd);
 	}
 
 	log_debug("spawn: %s -- %s", wp->shell, wp->cmd);
@@ -774,7 +774,7 @@ window_pane_spawn(struct window_pane *wp, const char *cmd, const char *shell,
 		xasprintf(cause, "%s: %s", cmd, strerror(errno));
 		return (-1);
 	case 0:
-		if (chdir(wp->cwd) != 0)
+		if (fchdir(wp->cwd) != 0)
 			chdir("/");
 
 		if (tcgetattr(STDIN_FILENO, &tio2) != 0)