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c++clinuxposix

How to get the username in C/C++ in Linux?

How can I get the actual "username" without using the environment (getenv, ...) in a program? Environment is C/C++ with Linux.

Solution

  • The function getlogin_r() defined in unistd.h returns the username. See man getlogin_r for more information.

    Its signature is:

    int getlogin_r(char *buf, size_t bufsize);

    Needless to say, this function can just as easily be called in C or C++.