NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | SEE ALSO | COLOPHON

PCAP_INJECT(3PCAP)                                        PCAP_INJECT(3PCAP)

NAME         top

       pcap_inject, pcap_sendpacket - transmit a packet

SYNOPSIS         top

       #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         top

       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
       support sending packets; as pcap_open_live() doesn't have a flag to
       indicate 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 devices 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 unchanged 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.)

RETURN VALUE         top

       pcap_inject() returns the number of bytes written on success and -1
       on failure.

       pcap_sendpacket() returns 0 on success and -1 on failure.

       If -1 is returned, pcap_geterr() or pcap_perror() may be called with
       p as an argument to fetch or display the error text.

SEE ALSO         top

       pcap(3PCAP), pcap_geterr(3PCAP)

COLOPHON         top

       This page is part of the libpcap (packet capture library) project.
       Information about the project can be found at 
       ⟨http://www.tcpdump.org/⟩.  If you have a bug report for this manual
       page, see ⟨http://www.tcpdump.org/#patches⟩.  This page was obtained
       from the project's upstream Git repository 
       ⟨https://github.com/the-tcpdump-group/libpcap.git⟩ on 2017-09-15.  If
       you discover any rendering problems in this HTML version of the page,
       or you believe there is a better or more up-to-date source for the
       page, or you have corrections or improvements to the information in
       this COLOPHON (which is not part of the original manual page), send a
       mail to man-pages@man7.org

                               3 January 2014             PCAP_INJECT(3PCAP)