CODEWITHSUNDEEP
c++windowswinapioutputconsole-application
Simone Bondi
Simone Bondi

Reputation: 79

WriteConsoleOutputCharacter crashing the Console Application

When trying to use the WriteConsoleOutputCharacter function, the application crashes.

COORD pos;
pos.X = 0;
pos.Y = 0;

HANDLE buffer = GetStdHandle(STD_OUTPUT_HANDLE);
LPDWORD written;

char* str = "s";
WriteConsoleOutputCharacter(buffer, str, strlen(str), pos, written);

but the WriteConsole function works correctly:

WriteConsole(buffer1,str,strlen(str),written,NULL);

I'm not getting any error but the Windows "application stopped responding" notification, and i can't use a debugger since the IDE I'm using (Dev C++ 5.11) has a broken one.

Upvotes: 0

Views: 1322

Answers (1)

Some programmer dude
Some programmer dude

Reputation: 409166

Where is the variable written pointing? The function will dereference that argument to set the number of characters written. If the variable is not initialized it will have an indeterminate value, and be seemingly pointing at a random location, leading to undefined behavior when being dereferenced.

Instead use a plain DWORD and use the address-of operator &:

DWORD written;

WriteConsoleOutputCharacter(buffer, str, strlen(str), pos, &written);
//                                                         ^
//                         Note the address-of operator here

Or if you're not interested in how many characters were written, pass nullptr instead.

Upvotes: 2

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