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PCAP_INJECT(3PCAP)					    PCAP_INJECT(3PCAP)

NAME
       pcap_inject, pcap_sendpacket - transmit a packet

SYNOPSIS
       #include	<pcap/pcap.h>

       int pcap_inject(pcap_t *p, const	void *buf, size_t size);
       int pcap_sendpacket(pcap_t *p, const u_char *buf, int size);

DESCRIPTION
       pcap_inject()  sends  a	raw  packet through the	network	interface; buf
       points to the data of the packet, including the link-layer header,  and
       size is the number of bytes in the packet.

       Note  that,  even  if  you successfully open the	network	interface, you
       might not have permission to send packets on it,	or it might  not  sup-
       port  sending  packets; as pcap_open_live(3PCAP)	doesn't	have a flag to
       indicate	whether	to open	for capturing, sending,	or capturing and send-
       ing, you	cannot request an open that supports sending and  be  notified
       at open time whether sending will be possible.  Note also that some de-
       vices might not support sending packets.

       Note  that,  on	some  platforms,  the  link-layer header of the	packet
       that's sent might not be	the same  as  the  link-layer  header  of  the
       packet  supplied	to pcap_inject(), as the source	link-layer address, if
       the header contains such	an address, might be changed to	be the address
       assigned	to the interface on which the packet it	sent, if the  platform
       doesn't	support	 sending  completely  raw and unchanged	packets.  Even
       worse, some drivers on some platforms might change the link-layer  type
       field to	whatever value libpcap used when attaching to the device, even
       on  platforms  that do nominally	support	sending	completely raw and un-
       changed packets.

       pcap_sendpacket() is like pcap_inject(),	but it returns 0  on  success,
       rather  than  returning	the  number  of	bytes written.	(pcap_inject()
       comes from OpenBSD; pcap_sendpacket() comes from	 WinPcap/Npcap.	  Both
       are provided for	compatibility.)

RETURN VALUE
       pcap_inject()  returns the number of bytes written on success, PCAP_ER-
       ROR_NOT_ACTIVATED if called on a	capture	handle that has	 been  created
       but not activated, and PCAP_ERROR on other errors.

       pcap_sendpacket()  returns  0  on  success, PCAP_ERROR_NOT_ACTIVATED if
       called on a capture handle that has been	created	but not	activated, and
       PCAP_ERROR on other errors.

       If PCAP_ERROR is	returned, pcap_geterr(3PCAP) or	pcap_perror(3PCAP) may
       be called with p	as an argument to fetch	or display the error text.

SEE ALSO
       pcap(3PCAP)

				 5 March 2022		    PCAP_INJECT(3PCAP)

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