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<SOLVED> ios::app, or ios::out clearing file data?

Consider a file 'new.txt' with these contents 0 Hello then I run this code(c++): fstream file("new.txt",ios::out); file<<1; file.close(); file.open("new.txt,ios::app|ios::out); file<<"\nBye"; Since I'm using ios::app mode I should be writing to the end of the file. So after I run the code it should be: 1 Hello Bye But instead that's what happens: 1 Bye I have tryed other methods too to write to the end of the file like file.clear(); file.seekg(ios::end); But nothing works as it should... Any suggestions?

28th Feb 2020, 11:52 AM
xaralampis_
xaralampis_ - avatar
2 Réponses
+ 4
Aren't you implicitly truncating the file with the first open?
28th Feb 2020, 12:31 PM
Dennis
Dennis - avatar
+ 4
Dennis Yeah i figured it out after a lot of testing. I didn't know that ios::out had these consiquencies. Thank you
28th Feb 2020, 12:47 PM
xaralampis_
xaralampis_ - avatar