How do I execute a Shell built-in command with a C function?

c shell command exec pwd
user2851770 picture user2851770 · Oct 6, 2013 · Viewed 120.4k times · Source

I would like to execute the Linux command "pwd" through a C language function like execv().

The issue is that there isn't an executable file called "pwd" and I'm unable to execute "echo $PWD", since echo is also a built-in command with no executable to be found.

Answer

smRaj picture smRaj · Oct 6, 2013

If you just want to execute the shell command in your c program, you could use,

   #include <stdlib.h>

   int system(const char *command);

In your case, 

system("pwd");

The issue is that there isn't an executable file called "pwd" and I'm unable to execute "echo $PWD", since echo is also a built-in command with no executable to be found.

What do you mean by this? You should be able to find the mentioned packages in /bin/

sudo find / -executable -name pwd
sudo find / -executable -name echo

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