Change the Current Working Directory in C++

Is there any way to change directory using C language?

Depending on your OS there are different calls for changing the current directory. These will normally only change the current dir of the process running the executable. After the process exits you will be in the directory you started in.

Change current working directory in child process in C

You have two mistakes,

• Usage of scanf()
• Not waiting for child to finish its task as parent.

The following works.

#include <unistd.h>
#include <stdio.h>
#include <errno.h>
#include <stdlib.h>
#include <sys/stat.h>

int main()
{
    int pid;
    char directory[1024];
    char newdirectory[1024];
    pid=fork();
    if(pid<0)
    {
        printf("\n Error ");
        exit(1);
    }
    else if(pid==0)
    {
        printf("I'm child \n ");
        printf(" My PID: %d \n",getpid());
        getcwd(directory, sizeof(directory));
        printf(" My current working directory is: %s\n", directory);
        printf(" Enter the new path\n");
        scanf("%1023s", newdirectory);
        chdir(newdirectory);
        getcwd(directory, sizeof(directory));
        printf(" Path changed to: %s\n", directory);
        exit(0);
    }
    else
    {
        wait(0);
        printf("I'm a parent \n ");
        printf("My PID is %d \n ",getpid());
        printf("Bye bye \n");
        exit(1);
    }
}

Change the current working directory in C++

The chdir function works on both POSIX (manpage) and Windows (called _chdir there but an alias chdir exists).

Both implementations return zero on success and -1 on error. As you can see in the manpage, more distinguished errno values are possible in the POSIX variant, but that shouldn't really make a difference for most use cases.

Is using chdir() the only way to change the working directory in Linux C?

chdir() is the only way to change the current working directory of the process. If you are not allowed to use this function you can partially simulate chdir() by keeping track of the current directory in the application, e.g. by using a variable. Note that such a simulation will not be complete, in particular the working directory of child processes will be where your program was started, not then one in your variable.

How can I change the shell directory in the C language program?

You cannot do that (changing your parent shell directory from inside a C program). The current directory is an attribute of every process, and your shell runs in a different process than your program (so the shell process and your program's process have each their own current directory).

Read Advanced Linux Programming. It has several chapters related to your issue.

Perhaps you might add some shell function (e.g. into your ~/.bashrc ...) which perhaps could use eval to run your C program (which would output some cd command, that the eval or source builtin of your shell would handle within the same shell process); BTW ssh-agent might be inspirational. Actually I don't recommend this route if you are a newbie.

PS. You really should motivate your question and give a lot more context; it smells badly like an XY problem.

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