Manpage of PCAP_SET_IMMEDIATE_MODE
Section: Misc. Reference Manual Pages (3PCAP)
Updated: 22 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.
pcap(3PCAP), pcap_create(3PCAP), pcap_activate(3PCAP)
This document was created by
using the manual pages from "The Tcpdump Group" git repositories.
Time: 06:01:47 GMT, August 23, 2018