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.TH PCAP_LIST_DATALINKS 3PCAP "5 April 2008"
.SH NAME
pcap_list_datalinks \- get a list of link-layer header types supported
by a capture device
.SH SYNOPSIS
.nf
.ft B
#include <pcap/pcap.h>
.ft
.LP
.ft B
int pcap_list_datalinks(pcap_t *p, int **dlt_buf);
.ft
.fi
.SH DESCRIPTION
.B pcap_list_datalinks()
is used to get a list of the supported data link types of the interface
associated with the pcap descriptor.
.B pcap_list_datalinks()
allocates an array to hold the list and sets
.IR *dlt_buf .
The caller is responsible for freeing the array with
.BR pcap_free_datalinks (3PCAP).
.SH RETURN VALUE
.B pcap_list_datalinks()
returns the number of data link types in the array on success and \-1
on failure.
If \-1 is returned,
.B pcap_geterr()
or
.B pcap_perror()
may be called with
.I p
as an argument to fetch or display the error text.
.SH SEE ALSO
pcap(3PCAP), pcap_geterr(3PCAP), pcap_free_datalinks(3PCAP),
pcap-linktype(7)