ESP32 Forum

Posted: **Sat Feb 03, 2024 1:46 pm**

Hi
I have a program that issues at midnight the summary of the past day.
It should issue the summary in a line appended to a file. That file should be in the csv format, for post processing in Excel.
All is done now.

But I would like to begin the line with a date identifier. Only day/month. And that identifier should be the day of yesterday (because I print after midnight)
Has someone got an idea how to code that in c++?

Thank you for any hint...

Posted: **Sat Feb 03, 2024 9:39 pm**

Finally I found out alone.

Code: [Select all] [Expand/Collapse]

//***Variables for Time***
tm* timeinfo;  
tm* yesterdaytimeinfo;  
time_t now;
time_t yesterdaynow;
static char charbuff[120];  //Char buffer for many functions
 
 
//*** In program ***
yesterdaynow = now - 86400;
yesterdaytimeinfo = localtime(&yesterdaynow);
strftime(charbuff, 30, "%x ", yesterdaytimeinfo);
println();
print(charbuff);

Enjoy!

ESP32 Forum

How to print the date of yesterday?

How to print the date of yesterday?

Re: How to print the date of yesterday?