Skip site navigation (1)Skip section navigation (2)

  
 
  

home | help
PCAP_SET_IMMEDIATE_MODE(3PCAP)			  PCAP_SET_IMMEDIATE_MODE(3PCAP)

NAME
     pcap_set_immediate_mode  -  set immediate mode for a not-yet-activated cap-
     ture handle

SYNOPSIS
     #include <pcap/pcap.h>

     int pcap_set_immediate_mode(pcap_t *p, int immediate_mode);

DESCRIPTION
     pcap_set_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.  If immedi-
     ate_mode is non-zero, immediate mode will be set, otherwise it will not  be
     set.

RETURN VALUE
     pcap_set_immediate_mode()	returns  0 on success or PCAP_ERROR_ACTIVATED if
     called on a capture handle that has been activated.

BACKWARD COMPATIBILITY
     This function became available in libpcap release 1.5.0.  In  previous  re-
     leases, 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 BIOCIMMEDIATE  ioctl(2),  as
	    documented	  in	bpf(4),    on	the   descriptor   returned   by
	    pcap_fileno(3PCAP), after pcap_activate(3PCAP) is called;

	    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  plat-
	    forms, so don't assume it's sufficient);

	    on	Digital UNIX/Tru64 UNIX, immediate mode must be turned on by do-
	    ing a BIOCMBIC ioctl(), as documented in packetfilter(7),  to  clear
	    the  ENBATCH  flag on the descriptor returned by pcap_fileno(3PCAP),
	    after pcap_activate(3PCAP) is called;

	    on Windows, immediate mode must be turned on  by  calling  pcap_set-
	    mintocopy() 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,  not  in
     immediate	mode, so if pcap_set_immediate_mode() is available, it should be
     used.

     On other platforms, capture devices are always in immediate mode.

SEE ALSO
     pcap(3PCAP), pcap_create(3PCAP), pcap_activate(3PCAP)

				 23 August 2018   PCAP_SET_IMMEDIATE_MODE(3PCAP)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=pcap_set_immediate_mode&sektion=3&manpath=FreeBSD+Ports+15.1.quarterly>

home | help