pcap_is_swapped.3pcap man page

#include <pcap/pcap.h>

int pcap_is_swapped(pcap_t *p);

pcap_is_swapped() returns true (1) if p refers to a “savefile” that uses a different byte order than the current system.  For a live capture, it always returns false (0).

It must not be called on a pcap descriptor created by pcap_create() that has not yet been activated by pcap_activate().

pcap_datalink() returns true (1) or false (0) on success and PCAP_ERROR_NOT_ACTIVATED if called on a capture handle that has been created but not activated.

pcap(3PCAP)