Expanding a relative path to a full path when running a C program in shell

Question

I have a problem when my script needs to communicate with a C executable. I cannot get the script's full path, which I need to load and send to another process.

The script's name is myScript

#!/home/user/git/proyect/test

hello this

is a
script

and this is the source code of the C executable

#include <stdio.h>

int main (int argc, char *argv[]){
    int count;

    printf ("Este programa fue llamado con: \"%s\".\n",argv[0]);
    if (argc > 1){
        for (count=1; count<argc; count++){
            printf("argv[%d] = %s\n", count, argv[count]);
        }
    }
    else{
        printf("The command had no other arguments.\n");
    }
    return 0;
 }

If I run myScript from terminal,

• argv[0] shows the executable's path (I guess that's because it's the info at #!).
• argv[1] shows the first argument passed to the executable, i.e.
  • if I use ./myScript as the argument, that is what I see (the relative path)
  • if I use /home/user/git/proyect/test/scriptFolder/myScript as the argument, it shows the absolute path (which is what I need, but I don't want to write the full path in terminal every time)

So my question is, how do I get the full path of myScript without passing its full path when calling the script?

Answer 1

Your question is not very well worded so I am not sure I am answering the same question that you are asking, but you can convert "./myScript" to its full path using the realpath() function.

Answer 2

As i understand you are implementing a script parser/interpreter.

The main function you present here is compiled and linked to the /home/user/git/proyect/test executable. Am i right?

That means that when you execute ./myScript on the terminal what is actually executed is /home/user/git/proyect/test ./myScript.

If this is the case @MK's answer is right. And with realpath() you can get the absolute path of "./myScript"

I would suggest editing your question to be more readable.