Epoch & Unix Timestamp in C

Get the current epoch timestamp

#include <time.h>

time_t epoch_seconds = time(NULL);

Convert epoch to date

time_t ts = 1718200000;
struct tm *utc = gmtime(&ts);
char buf[32];
strftime(buf, sizeof buf, "%Y-%m-%d %H:%M:%S", utc);

Convert date to epoch

struct tm tm = {0};
tm.tm_year = 2026 - 1900; tm.tm_mon = 5; tm.tm_mday = 12;
time_t epoch = timegm(&tm);