[W]
WAKEUP_CHARS
WCOREDUMP
WEXITSTATUS
WIFEXITED
WIFSIGNALED
WIFSTOPPED
WIN_DIAGNOSE
WIN_FORMAT
WIN_INIT
WIN_READ
WIN_RESTORE
WIN_SEEK
WIN_SPECIFY
WIN_VERIFY
WIN_WRITE
WNOHANG
WRERR_STAT
WRITE
WRITEA
WSTOPSIG
WTERMSIG
WUNTRACED
W_OK