Fix (un)setenv to not return an error with unset env vars.

The code was returning -1 in those cases.  This can cause hook
processors, such as send2-hook, to sleep 1 second without an error
message being set and displayed.  It also causes the hook processor to
abort executing subsequent matching commands.

-1 should be reserved for syntax errors.  For setenv querying, change
the return value to 0.  For unsetenv, generate a message and also
change the return value to 0.

<enter-command> checks if err->data is set to determine whether to
print anything, and the behavior is used in the 'set' commands, so
this is established correct behavior.

1 files changed, 4 insertions, 2 deletions

diff --git a/init.c b/init.c
index 4e6ff9be..e9ecc3cf 100644
--- a/init.c
+++ b/init.c
@@ -2144,7 +2144,7 @@ static int parse_setenv(BUFFER *tmp, BUFFER *s, union pointer_long_t udata, BUFF
     }
 
     snprintf (err->data, err->dsize, _("%s is unset"), tmp->data);
-    return -1;
+    return 0;
   }
 
   if (unset)
@@ -2168,7 +2168,9 @@ static int parse_setenv(BUFFER *tmp, BUFFER *s, union pointer_long_t udata, BUFF
       envp++;
       count++;
     }
-    return -1;
+
+    snprintf (err->data, err->dsize, _("%s is unset"), tmp->data);
+    return 0;
   }
 
   /* set variable */