Add psql PROMPT variable showing the pid of the connected to backend.

The substitution for the pid is %p.

Author: Julien Rouhaud
Discussion: 116262CF971C844FB6E793F8809B51C6E99D48@BPXM02GP.gisp.nec.co.jp

diff --git a/doc/src/sgml/ref/psql-ref.sgml b/doc/src/sgml/ref/psql-ref.sgml
index d17d405f20fb1e47c9ad3e2f3ca1607ae43fb893..ac609fdf56a87389ee1d9f8952a3f41c18fc6370 100644 (file)
--- a/doc/src/sgml/ref/psql-ref.sgml
+++ b/doc/src/sgml/ref/psql-ref.sgml
@@ -3364,6 +3364,13 @@ testdb=&gt; <userinput>INSERT INTO my_table VALUES (:'content');</userinput>
         </listitem>
       </varlistentry>
 
+      <varlistentry>
+        <term><literal>%p</literal></term>
+        <listitem>
+         <para>The pid of the backend currently connected to.</para>
+        </listitem>
+      </varlistentry>
+
       <varlistentry>
         <term><literal>%&gt;</literal></term>
         <listitem><para>The port number at which the database server is listening.</para></listitem>

diff --git a/src/bin/psql/prompt.c b/src/bin/psql/prompt.c
index 89842673f87fce0160fe9f1d6b203321271a315e..96e669a6ff5caa82097689cddc67ac07cfcbc6a2 100644 (file)
--- a/src/bin/psql/prompt.c
+++ b/src/bin/psql/prompt.c
@@ -34,6 +34,7 @@
  * %M - database server "hostname.domainname", "[local]" for AF_UNIX
  *             sockets, "[local:/dir/name]" if not default
  * %m - like %M, but hostname only (before first dot), or always "[local]"
+ * %p - backend pid
  * %> - database server port number
  * %n - database user name
  * %/ - current database
@@ -161,6 +162,15 @@ get_prompt(promptStatus_t status)
                                        if (pset.db)
                                                strlcpy(buf, session_username(), sizeof(buf));
                                        break;
+                                       /* backend pid */
+                               case 'p':
+                                       if (pset.db)
+                                       {
+                                               int pid = PQbackendPID(pset.db);
+                                               if (pid)
+                                                       snprintf(buf, sizeof(buf), "%d", pid);
+                                       }
+                                       break;
 
                                case '0':
                                case '1':