How to print the date of yesterday?

[rin67630]

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...

[rin67630]

Finally I found out alone.

Code: [Select all] [Expand/Collapse]

1. //***Variables for Time***
2. tm* timeinfo;  
3. tm* yesterdaytimeinfo;  
4. time_t now;
5. time_t yesterdaynow;
6. static char charbuff[120];  //Char buffer for many functions
7.  
8.  
9. //*** In program ***
10. yesterdaynow = now - 86400;
11. yesterdaytimeinfo = localtime(&yesterdaynow);
12. strftime(charbuff, 30, "%x ", yesterdaytimeinfo);
13. println();
14. print(charbuff);

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