How to print to output (not stdout) in Linux (GCC)?

Question

On Windows there is OutputDebugString function, how do I do the same on Linux?

Update: stderr and stdlog is not what I want. Those are redirected to stdout. P. S. And syslog is no different.

Answer 1

I'm not sure what OutputDebugString does exactly, but standard C++ defines the standard error stream std::cerr and the standard logging stream std::clog. Both are declared in the header <iostream>.

These are by default tied to the same file descriptor in Linux; the difference is that cerr is unbuffered, while clog is buffered (I believe it's line-buffered).

There is no notion of a "system debugger" in Linux. If you want to write to the system log, you can use syslog(3).