GLib文档称g_file_has_key()、g_key_file_has_key()已废弃，替代函数何在？

Hey there! Let me clear up the confusion around these deprecated GLib functions—you’re not missing a brand new replacement function; instead, the same function names are still used, just with an updated parameter signature.

The Deprecation Breakdown #

The versions of g_file_has_key() and g_key_file_has_key() marked as deprecated are specifically the ones that accepted a GError **error parameter. GLib made this change because the error scenarios for these "check existence" functions are usually straightforward (like invalid file formatting or a missing group), so a simple boolean flag is enough instead of a full-fledged GError object.

The "Replacement" Is the Updated Function #

Instead of searching for a new function name, you just use the same function but swap the last parameter from GError ** to gboolean *error_out:

Example for g_key_file_has_key()

Old (deprecated) code:

GError *error = NULL;
gboolean has_key = g_key_file_has_key(keyfile, "MyAppSettings", "AutoSave", &error);
if (error != NULL) {
    g_printerr("Error checking key: %s\n", error->message);
    g_error_free(error);
}

New (supported) code:

gboolean error_occurred = FALSE;
gboolean has_key = g_key_file_has_key(keyfile, "MyAppSettings", "AutoSave", &error_occurred);
if (error_occurred) {
    g_printerr("An error occurred while checking for the key!\n");
}

Key Notes #

• The gboolean *error_out parameter will be set to TRUE if any error happens during the check (invalid key file syntax, missing group, etc.).
• This updated approach doesn’t provide detailed error messages. If you need granular error information, you’ll want to validate the file first using other GLib functions (like g_key_file_load_from_file() with a GError) before checking for specific keys.

内容的提问来源于stack exchange，提问作者psprint