function log_set_always_fatal(fatal_mask: GLib.LogLevelFlags): GLib.LogLevelFlags {
    // Gjs wrapper for g_log_set_always_fatal()

Sets the message levels which are always fatal, in any log domain. When a message with any of these levels is logged the program terminates. You can only set the levels defined by GLib to be fatal. GLib.LogLevelFlags.level_error is always fatal.

You can also make some message levels fatal at runtime by setting the `G_DEBUG` environment variable (see [Running GLib Applications](glib-running.html)).


the mask containing bits set for each level of error which is to be fatal


the old fatal mask