File status flags are used to specify attributes of the opening of a
file. Unlike the file descriptor flags discussed in Descriptor Flags, the file status flags are shared by duplicated file descriptors
resulting from a single opening of the file. The file status flags are
specified with the flags argument to
see Opening and Closing Files.
File status flags fall into three categories, which are described in the following sections.
openand are returned by
fcntl, but cannot be changed.
openwill do. These flags are not preserved after the
writeare done. They are set by
open, and can be fetched or changed with
The symbols in this section are defined in the header file fcntl.h.