module os // File modes const ( o_rdonly = 000000000 // open the file read-only. o_wronly = 000000001 // open the file write-only. o_rdwr = 000000002 // open the file read-write. o_create = 000000100 // create a new file if none exists. o_binary = 000008000 // input and output is not translated. o_excl = 000000200 // used with o_create, file must not exist. o_noctty = 000000400 // if file is terminal, don't make it the controller terminal o_trunc = 000001000 // truncate regular writable file when opened. o_append = 000002000 // append data to the file when writing. o_nonblock = 000004000 // prevents blocking when opening files o_sync = 000010000 // open for synchronous I/O. )