FD_SETSIZE 1024U

Description

The value of this macro is the maximum number of file descriptors that a fd_setfd_set object can hold information about.

FD_CLR (n, p) ((p)->__fds_bits[(n)/_NFDBITS] &= ~__fdset_mask(n))

Description

Clears the bit for the file descriptor fd in the file descriptor set fdset.

Parameters

FD_ISSET (n, p) ((p)->__fds_bits[(n)/_NFDBITS] & __fdset_mask(n))

Description

Returns a non-zero value if the bit for the file descriptor fd is set in the file descriptor set pointed to by fdset, and 0 otherwise.

Parameters

FD_SET (n, p) ((p)->__fds_bits[(n)/_NFDBITS] |= __fdset_mask(n))

Description

Sets the bit for the file descriptor fd in the file descriptor set fdset.

Parameters

FD_ZERO (p) do {                    \
    fd_set *_p;                 \
    __size_t _n;                    \
                            \
    _p = (p);                   \
    _n = _howmany(FD_SETSIZE, _NFDBITS);        \
    while (_n > 0)                   \
        _p->__fds_bits[--_n] = 0;        \
} while (0)

Description

Initialises the file descriptor set fdset to have zero bits for all file descriptors.

Parameters

typedef __sigset_t sigset_t;

Description

The sigset_t data type is used to represent a signal set.