#include struct pcap_file_header { long magic; u_short version_major; u_short version_minor; long thiszone; u_long sigfigs; u_long snaplen; u_long linktype; }; int main (void) { struct pcap_file_header file_header = {0}; FILE *fp = NULL; fp = fopen ("/tmp/pflog", "rb"); if (fread(&file_header.magic, sizeof(file_header.magic),1,fp) == NULL) { printf("error reading magic!\n"); return(1); } printf("%d\n", file_header.magic); fclose(fp); return 0; }