Implement !local in guestfish.

fish/fish.c

@@ -26,6 +26,7 @@
 #include <unistd.h>
 #include <fcntl.h>
 #include <getopt.h>
+#include <signal.h>
 #include <assert.h>
 
 #ifdef HAVE_LIBREADLINE
@@ -359,6 +360,21 @@ script (int prompt)
     /* If the next character is '#' then this is a comment. */
     if (*buf == '#') continue;
 
+    /* If the next character is '!' then pass the whole lot to system(3). */
+    if (*buf == '!') {
+      int r;
+
+      r = system (buf+1);
+      if (!prompt) {
+	if (r == -1 ||
+	    (WIFSIGNALED (r) &&
+	     (WTERMSIG (r) == SIGINT || WTERMSIG (r) == SIGQUIT)) ||
+	    WEXITSTATUS (r) != 0)
+	  exit (1);
+      }
+      continue;
+    }
+
     /* Get the command (cannot be quoted). */
     len = strcspn (buf, " \t");
 

guestfish.pod

@@ -189,6 +189,19 @@ but B<not> by a command.  For example:
 
 Blank lines are also ignored.
 
+=head1 RUNNING COMMANDS LOCALLY
+
+Any line which starts with a I<!> character is treated as a command
+sent to the local shell (C</bin/sh> or whatever L<system(3)> uses).
+For example:
+
+ !mkdir local
+ tgz-out /remote local/remote-data.tar.gz
+
+will create a directory C<local> on the host, and then export
+the contents of C</remote> on the mounted filesystem to
+C<local/remote-data.tar.gz>.  (See C<tgz-out>).
+
 =head1 COMMANDS
 
 =head2 help