errno_value [function]

errno_value( string key )

returns the number for the error key (for "ENOENT" it would return 2)

• this function might be a bit slow considering that it currently does not use any extended lookup systems, such as hash tables

data = io_file_read( "doesnotexist" );
if( errno() == error_string("ENOENT") )
    println( "file does not exist" );