dayStr/monthStr problem

[Haps]

I am using TimerLib for the ESP32 platform and I am getting peculiar output from dayStr/monthStr functions.

sprintf(buffer,”%s, %02d %s %04d",dayStr(day(timer_counter)),day(timer_counter), monthStr(month(timer_counter)),year(timer_counter));
Serial.println(buffer);

The output is January, 01 January 1970. I thought that the dayStr(day(timer)counter) should show a day of the week at 01/01/1970 (Thursday). Could you advise what is wrong?

Adafruit Feather/Metro/Trinket: forums.adafruit.com
Particle Photon: community.particle.io

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