agent: Add command "getinfo std_env_names".

* agent/command.c (cmd_getinfo): Add new sub-command.
--

The current output is:

  > getinfo std_env_names
  D GPG_TTY
  D TERM
  D DISPLAY
  D XAUTHORITY
  D XMODIFIERS
  D GTK_IM_MODULE
  D QT_IM_MODULE
  D PINENTRY_USER_DATA
  OK

Note that there is an invisible \x00 at the end of each line.

1 files changed, 16 insertions, 0 deletions

diff --git a/agent/command.c b/agent/command.c
index f71325d55..82d93e954 100644
--- a/agent/command.c
+++ b/agent/command.c
@@ -2756,6 +2756,7 @@ static const char hlp_getinfo[] =
   "  ssh_socket_name - Return the name of the ssh socket.\n"
   "  scd_running - Return OK if the SCdaemon is already running.\n"
   "  s2k_count   - Return the calibrated S2K count.\n"
+  "  std_env_names   - List the names of the standard environment.\n"
   "  std_session_env - List the standard session environment.\n"
   "  std_startup_env - List the standard startup environment.\n"
   "  cmd_has_option\n"
@@ -2849,6 +2850,21 @@ cmd_getinfo (assuan_context_t ctx, char *line)
     {
       rc = agent_scd_check_running ()? 0 : gpg_error (GPG_ERR_GENERAL);
     }
+  else if (!strcmp (line, "std_env_names"))
+    {
+      int iterator;
+      const char *name;
+
+      iterator = 0;
+      while ((name = session_env_list_stdenvnames (&iterator, NULL)))
+        {
+          rc = assuan_send_data (ctx, name, strlen (name)+1);
+          if (!rc)
+            rc = assuan_send_data (ctx, NULL, 0);
+          if (rc)
+            break;
+        }
+    }
   else if (!strcmp (line, "std_session_env")
            || !strcmp (line, "std_startup_env"))
     {