pcap_init(3pcap) — Linux manual page


PCAP_INIT(3PCAP)                                        PCAP_INIT(3PCAP)

NAME         top

       pcap_init - initialize the library

SYNOPSIS         top

       #include <pcap/pcap.h>

       char errbuf[PCAP_ERRBUF_SIZE];

       int pcap_init(unsigned int opts, char *errbuf);

DESCRIPTION         top

       pcap_init() is used to initialize the Packet Capture library.
       opts specifies options for the library; currently, the options

              Map packet buffers with 32-bit addresses.

              Treat all strings supplied as arguments, and return all
              strings to the caller, as being in the local character

              Treat all strings supplied as arguments, and return all
              strings to the caller, as being in UTF-8.

       On UNIX-like systems, the local character encoding is assumed to
       be UTF-8, so no character encoding transformations are done.

       On Windows, the local character encoding is the local ANSI code

       If pcap_init() is not called, strings are treated as being in the
       local ANSI code page on Windows, pcap_lookupdev(3PCAP) will
       succeed if there is a device on which to capture, and
       pcap_create(3PCAP) makes an attempt to check whether the string
       passed as an argument is a UTF-16LE string - note that this
       attempt is unsafe, as it may run past the end of the string - to
       handle pcap_lookupdev() returning a UTF-16LE string. Programs
       that don't call pcap_init() should, on Windows, call
       pcap_wsockinit() to initialize Winsock; this is not necessary if
       pcap_init() is called, as pcap_init() will initialize Winsock
       itself on Windows.

RETURN VALUE         top

       pcap_init() returns 0 on success and PCAP_ERROR on failure.  If
       PCAP_ERROR is returned, errbuf is filled in with an appropriate
       error message.  errbuf is assumed to be able to hold at least
       PCAP_ERRBUF_SIZE chars.


       This function became available in libpcap release 1.9.0.  In
       previous releases, on Windows, all strings supplied as arguments,
       and all strings returned to the caller, are in the local
       character encoding.

SEE ALSO         top


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 2023-06-23.
       (At that time, the date of the most recent commit that was found
       in the repository was 2023-06-21.)  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

                             17 January 2023            PCAP_INIT(3PCAP)