Convert string from __DATE__ into a time_t

Question

I\'m trying to convert the string produced from the __DATE__ macro into a time_t. I don\'t need a full-blown date/time parser, something that only han

Answer 1

Bruno's response was very useful for my Arduino Project. Here is a version with both __DATE__ and __TIME__

#include <Time.h>
#include <stdio.h>

time_t cvt_date(char const *date, char const *time)
{
    char s_month[5];
    int year;
    tmElements_t t;
    static const char month_names[] = "JanFebMarAprMayJunJulAugSepOctNovDec";

    sscanf(date, "%s %hhd %d", s_month, &t.Day, &year);
    sscanf(time, "%2hhd %*c %2hhd %*c %2hhd", &t.Hour, &t.Minute, &t.Second);

    // Find where is s_month in month_names. Deduce month value.
    t.Month = (strstr(month_names, s_month) - month_names) / 3 + 1;

    // year can be given as '2010' or '10'. It is converted to years since 1970
    if (year > 99) t.Year = year - 1970;
    else t.Year = year + 30;

    return makeTime(t);
}

void setup()
{
    Serial.begin(115200); 
    while (!Serial);

    // Show raw system strings
    Serial.println(String("__DATE__ = ") + __DATE__);
    Serial.println(String("__TIME__ = ") + __TIME__);

    // set system time = compile time
    setTime(cvt_date(__DATE__, __TIME__));

    // Show actual time
    Serial.println(String("System date = ") + month() + "/" + day() + "/" + year() + " " + hour() + ":" + minute() + ":" + second() + "\n");
}

void loop() {}