Git - Perform Changes

Jerry clones the repository and decides to implement basic string operations. So he creates string.c file. After adding the contents, string.c will look like as follows −

#include <stdio.h>

int my_strlen(char *s)
{
   char *p = s;

   while (*p)
      ++p;

   return (p - s);
}

int main(void)
{
   int i;
   char *s[] = 
   {
      "Git tutorials",
      "Tutorials Point"
   };

   for (i = 0; i < 2; ++i)
      
   printf("string lenght of %s = %d\n", s[i], my_strlen(s[i]));

   return 0;
}

He compiled and tested his code and everything is working fine. Now, he can safely add these changes to the repository.

Git add operation adds file to the staging area.

[jerry@CentOS project]$ git status -s
?? string
?? string.c

[jerry@CentOS project]$ git add string.c

Git is showing a question mark before file names. Obviously, these files are not a part of Git, and that is why Git does not know what to do with these files. That is why, Git is showing a question mark before file names.

Jerry has added the file to the stash area, git status command will show files present in the staging area.

[jerry@CentOS project]$ git status -s
A string.c
?? string

To commit the changes, he used the git commit command followed by m option. If we omit m option. Git will open a text editor where we can write multiline commit message.

[jerry@CentOS project]$ git commit -m 'Implemented my_strlen function'

The above command will produce the following result −

[master cbe1249] Implemented my_strlen function
1 files changed, 24 insertions(+), 0 deletions(-)
create mode 100644 string.c

After commit to view log details, he runs the git log command. It will display the information of all the commits with their commit ID, commit author, commit date and SHA-1 hash of commit.

[jerry@CentOS project]$ git log

The above command will produce the following result −

commit cbe1249b140dad24b2c35b15cc7e26a6f02d2277
Author: Jerry Mouse <jerry@tutorialspoint.com>
Date: Wed Sep 11 08:05:26 2013 +0530

Implemented my_strlen function


commit 19ae20683fc460db7d127cf201a1429523b0e319
Author: Tom Cat <tom@tutorialspoint.com>
Date: Wed Sep 11 07:32:56 2013 +0530

Initial commit