module os // File modes const ( o_rdonly = 0o00000000 // open the file read-only. o_wronly = 0o00000001 // open the file write-only. o_rdwr = 0o00000002 // open the file read-write. o_binary = 0o00000000 // input and output is not translated; the default on unix o_create = 0o00000100 // create a new file if none exists. o_excl = 0o00000200 // used with o_create, file must not exist. o_noctty = 0o00000400 // if file is terminal, don't make it the controller terminal o_trunc = 0o00001000 // truncate regular writable file when opened. o_append = 0o00002000 // append data to the file when writing. o_nonblock = 0o00004000 // prevents blocking when opening files o_sync = 0o04010000 // open for synchronous I/O. )