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PCAP_GET_REQUIRED_SELECT_TILibrary)FunctionPCAP_GET_REQUIRED_SELECT_TIMEOUT(3)

NAME
       pcap_get_required_select_timeout	- get a	file descriptor	on which a se-
       lect() can be done for a	live capture

SYNOPSIS
       #include	<pcap/pcap.h>

       struct timeval *pcap_get_required_select_timeout(pcap_t *p);

DESCRIPTION
       pcap_get_required_select_timeout() returns, on UNIX,  a	pointer	 to  a
       struct  timeval	containing  a  value  that must	be used	as the minimum
       timeout in  select(),  poll(),  epoll_wait(),  and  kevent()  calls  if
       pcap_get_selectable_fd()	returns	-1.

       The  timeout  that should be used in those calls	must be	no larger than
       the smallest of all timeouts returned by	pcap_get_required_select_time-
       out() for devices from which packets will be captured.

       The  device  for	which pcap_get_selectable_fd() returned	-1 must	be put
       in non-blocking mode with pcap_setnonblock(), and an attempt  must  al-
       ways be made to read packets from the device when the select(), poll(),
       epoll_wait(), or	kevent() call returns.

       Note that a device on which a read can be done without blocking may, on
       some platforms, not have	any packets to read if the packet buffer time-
       out has expired.	 A call	to pcap_dispatch() or pcap_next_ex() will  re-
       turn 0 in this case, but	will not block.

       pcap_get_required_select_timeout() is not available on Windows.

RETURN VALUE
       A  pointer  to a	struct timeval is returned if the timeout is required;
       otherwise NULL is returned.

SEE ALSO
       pcap(3),	pcap_get_selectable_fd(3), select(2), poll(2),	epoll_wait(2),
       kqueue(2)

				19 January PCAP_GET_REQUIRED_SELECT_TIMEOUT(3)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | SEE ALSO

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