std::source_location::file_name
From cppreference.com
                    
                                        
                    < cpp | utility | source location
                    
                                                            
                    |   constexpr const char* file_name() const noexcept;  | 
(since C++20) | |
Returns the name of the current source file represented by this object, represented as a null-terminated byte string.
Parameters
(none)
Return value
The name of the current source file represented by this object, represented as a null-terminated byte string.
Example
Run this code
#include <iostream> #include <source_location> void print_this_file_name( std::source_location location = std::source_location::current()) { // Name of file that contains the call site of this function. std::cout << "File: " << location.file_name() << '\n'; } int main() { #line 1 "cppreference.cpp" print_this_file_name(); }
Output:
File: cppreference.cpp
See also
|   return the line number represented by this object  (public member function)  | |
|   return the column number represented by this object  (public member function)  | |
|   return the name of the function represented by this object, if any  (public member function)  | |
  gets the name of the source file that lexically contains the expression or statement whose evaluation is represented by the stacktrace_entry (public member function of std::stacktrace_entry)  | |
| Filename and line information | |