C/C++ line number

Question

In the sake of debugging purposes, can I get the line number in C/C++ compilers? (standard way or specific ways for certain compilers)

e.g

if(!Logical)
    printf("Not logical value at line number %d \n",LineNumber);
    // How to get LineNumber without writing it by my hand?(dynamic compilation)

Answer 1

You could use a macro with the same behavior as printf(), except that it also includes debug information such as function name, class, and line number:

#include <cstdio>  //needed for printf
#define print(a, args...) printf("%s(%s:%d) " a,  __func__,__FILE__, __LINE__, ##args)
#define println(a, args...) print(a "\n", ##args)

These macros should behave identically to printf(), while including java stacktrace-like information. Here's an example main:

void exampleMethod() {
    println("printf() syntax: string = %s, int = %d", "foobar", 42);
}

int main(int argc, char** argv) {
    print("Before exampleMethod()...\n");
    exampleMethod();
    println("Success!");
}

Which results in the following output:

main(main.cpp:11) Before exampleMethod()...
exampleMethod(main.cpp:7) printf() syntax: string = foobar, int = 42
main(main.cpp:13) Success!