[gnome-session] Valid error numbers are all positive numbers

[Benjamin Berg <bberg src gnome org>]

commit 534850d20b4f9dcb2c521bf6420a4d34123e7893
Author: Xiaoguang Wang <xwang suse com>
Date:   Fri Apr 10 15:41:23 2020 +0800

    Valid error numbers are all positive numbers
    
    There is error in journal log:
    gnome-session-c[4905]: Error creating FIFO: File exists
    The errno can't be negative number.
    
    https://gitlab.gnome.org/GNOME/gnome-session/-/merge_requests/42

 gnome-session/main.c      | 2 +-
 tools/gnome-session-ctl.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/gnome-session/main.c b/gnome-session/main.c
index 01f56667..c1dda5dc 100644
--- a/gnome-session/main.c
+++ b/gnome-session/main.c
@@ -349,7 +349,7 @@ systemd_leader_run(void)
         fifo_name = g_strdup_printf ("%s/gnome-session-leader-fifo",
                                      g_get_user_runtime_dir ());
         res = mkfifo (fifo_name, 0666);
-        if (res < 0 && errno != -EEXIST)
+        if (res < 0 && errno != EEXIST)
                 g_warning ("Error creating FIFO: %m");
 
         fifo_fd = g_open (fifo_name, O_WRONLY | O_CLOEXEC, 0666);
diff --git a/tools/gnome-session-ctl.c b/tools/gnome-session-ctl.c
index 9276a0ad..86f03be1 100644
--- a/tools/gnome-session-ctl.c
+++ b/tools/gnome-session-ctl.c
@@ -194,7 +194,7 @@ do_monitor_leader (void)
         fifo_name = g_strdup_printf ("%s/gnome-session-leader-fifo",
                                      g_get_user_runtime_dir ());
         res = mkfifo (fifo_name, 0666);
-        if (res < 0 && errno != -EEXIST)
+        if (res < 0 && errno != EEXIST)
                 g_warning ("Error creating FIFO: %m");
 
         data.fifo_fd = g_open (fifo_name, O_RDONLY | O_CLOEXEC, 0666);