GLib.strerror

function strerror(errnum: Number(gint)): String {
    // Gjs wrapper for g_strerror()
}

Returns a string corresponding to the given error code, e.g. "no such process". You should use this function in preference to strerror(), because it returns a string in UTF-8 encoding, and since not all platforms support the strerror() function.

errnum: the system error number. See the standard C %errno documentation
Returns: a UTF-8 string describing the error code. If the error code is unknown, it returns "unknown error (<code>)".