How can we know the caller function's name?

Question

In the C language, __FUNCTION__ can be used to get the current function\'s name. But if I define a function named a() and it is called

Answer 1

You can do it with a gcc builtin.

void * __builtin_return_address(int level)

The following way should print the immediate caller of a function a().

Example:

a() {
    printf ("Caller name: %pS\n", __builtin_return_address(0));
}

Answer 2

Refer: https://www.gnu.org/software/libc/manual/html_node/Backtraces.html

A backtrace is a list of the function calls that are currently active in a thread. The usual way to inspect a backtrace of a program is to use an external debugger such as gdb. However, sometimes it is useful to obtain a backtrace programmatically from within a program, e.g., for the purposes of logging or diagnostics.

The header file execinfo.h declares three functions that obtain and manipulate backtraces of the current thread.

Answer 3

If your platform is Windows, you may use this: walking the callstack

Answer 4

If you're only after knowing where you were for logging/debug purposes you can use a macro to avoid __func__ giving the name of your logging/debug function but of the function calling it.

Being in a macro will not result in a change to __func__ but will "feel" like using a function.

e.g.

#define LOG(s, data...) log("%s: "s, __function__, ## data)