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PCAP_LIST_DATALINKS(3) FreeBSD Library Functions Manual
NAME
pcap_list_datalinks, pcap_free_datalinks - get a list of link-layer
header types supported by a capture device, and free that list
SYNOPSIS
#include <pcap/pcap.h>
int pcap_list_datalinks(pcap_t *p, int **dlt_buf);
void pcap_free_datalinks(int *dlt_list);
DESCRIPTION
pcap_list_datalinks() is used to get a list of the supported link-layer
header types of the interface associated with the pcap descriptor.
pcap_list_datalinks() allocates an array to hold the list and sets
*dlt_buf to point to that array.
The caller is responsible for freeing the array with
pcap_free_datalinks(), which frees the list of link-layer header types
pointed to by dlt_list.
It must not be called on a pcap descriptor created by pcap_create(3)
that has not yet been activated by pcap_activate(3).
RETURN VALUE
pcap_list_datalinks() returns the number of link-layer header types in
the array 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(3) or pcap_perror(3)
may be called with p as an argument to fetch or display the error text.
SEE ALSO
pcap(3), pcap_datalink_val_to_name(3), pcap-linktype(7)
25 July 2018 PCAP_LIST_DATALINKS(3)