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PCAP_INJECT(3)		   Library Functions Manual		PCAP_INJECT(3)

       pcap_inject, pcap_sendpacket - transmit a packet

       #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);

       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(3) doesn't have a flag to indi-
       cate whether to open for	capturing, sending, or capturing and  sending,
       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.   Both  are
       provided	for compatibility.)

       pcap_inject()  returns  the  number  of	bytes  written	on success and
       PCAP_ERROR on failure.

       pcap_sendpacket() returns 0 on success and PCAP_ERROR on	failure.

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


				 25 July 2018			PCAP_INJECT(3)


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