Manpage of PCAP_SET_IMMEDIATE_MODE
Section: Misc. Reference Manual Pages (3PCAP)
Updated: 23 August 2018
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pcap_set_immediate_mode - set immediate mode for a not-yet-activated capture
int pcap_set_immediate_mode(pcap_t *p, int immediate_mode);
sets whether immediate mode should be set on a capture handle when
the handle is activated. In immediate mode, packets are always
delivered as soon as they arrive, with no buffering.
is non-zero, immediate mode will be set, otherwise it will not be set.
returns 0 on success or
if called on a capture handle that has been activated.
This function became available in libpcap release 1.5.0. In previous
releases, if immediate delivery of packets is required:
on FreeBSD, NetBSD, OpenBSD, DragonFly BSD, macOS, and Solaris 11,
immediate mode must be turned on with a
as documented in
on the descriptor returned by
on Solaris 10 and earlier versions of Solaris, immediate mode must be
turned on by using a read timeout of 0 when opening the device (this
will not provide immediate delivery of packets on other platforms, so
don't assume it's sufficient);
on Digital UNIX/Tru64 UNIX, immediate mode must be turned on by doing a
as documented in
to clear the
flag on the descriptor returned by
on Windows, immediate mode must be turned on by calling
with a size of 0.
On Linux, with previous releases of libpcap, capture devices are always
in immediate mode; however, in 1.5.0 and later, they are, by default,
in immediate mode, so if
is available, it should be used.
On other platforms, capture devices are always in immediate mode.
This document was created by
using the manual pages from "The Tcpdump Group" git repositories.
Time: 22:32:39 GMT, February 16, 2020