Get ID from user and group in Linux

Hi everyone,

Sometimes it handy to deal with id’s instead of actual names. It makes your commands shorter.
So if you ever need to get the id’s of one user or a group in Linux, here’s the commands to run:

– id -u USERNAME – will give you the USERNAME ID;
– id -a USERNAME – will give, not only the ID of the user, but also all the groups the user is part of;
– id -g USERNAME – will give the ID of the user’s primary group;
– id -G USERNAME – will give you the ID of all groups the user is a member of;

If you just want to know the id of a group, the just run:

cat /etc/group | grep GROUPNAME

The third item of the colon(:) separated string is the group ID.

And there you have it.
Now you can find out every user and group ID’s.

Enjoy.