2 files changed, 6 insertions, 0 deletions
diff --git a/README.pod b/README.pod
index 62a79d9..8c64540 100644
--- a/README.pod
+++ b/README.pod
@@ -126,6 +126,8 @@ The format argument allows the following interpreted sequences:
 
   %w    install reason
 
+  %!    result number (auto-incremented counter, starts at 0)
+
   %%    literal %
 
 Note that for any lowercase tokens aside from %m and %k, full printf support is
diff --git a/expac.c b/expac.c
index 85dcc19..ee057aa 100644
--- a/expac.c
+++ b/expac.c
@@ -57,6 +57,7 @@ const char *format = NULL;
 const char *timefmt = NULL;
 const char *listdelim = NULL;
 const char *delim = NULL;
+int pkgcounter = 0;
 
 typedef const char *(*extractfn)(void*);
 
@@ -406,6 +407,9 @@ static int print_pkg(pmpkg_t *pkg, const char *format) {
         case 'w': /* install reason */
           out += printf(fmt, alpm_pkg_get_reason(pkg) ? "dependency" : "explicit");
           break;
+        case '!': /* result number */
+          out += printf("%d", pkgcounter++);
+          break;
 
         /* times */
         case 'b': /* build date */