GLib-2.0 ▶ GLib ▶ log_writer_default_would_dropSince 2.68

Check whether GLib.log_writer_default and GLib.log_default_handler would ignore a message with the given domain and level.

As with GLib.log_default_handler, this function drops debug and informational messages unless their log domain (or all) is listed in the space-separated G_MESSAGES_DEBUG environment variable, or DEBUG_INVOCATION=1 is set in the environment, or by GLib.log_writer_default_set_debug_domains.

This can be used when implementing log writers with the same filtering behaviour as the default, but a different destination or output format:

if (g_log_writer_default_would_drop (log_level, log_domain))
  return G_LOG_WRITER_HANDLED;
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or to skip an expensive computation if it is only needed for a debugging message, and G_MESSAGES_DEBUG and DEBUG_INVOCATION are not set:

if (!g_log_writer_default_would_drop (G_LOG_LEVEL_DEBUG, G_LOG_DOMAIN))
  {
    g_autofree gchar *result = expensive_computation (my_object);

    g_debug ("my_object result: %s", result);
  }
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