How to add, delete edit username from /etc/passwd

Question

I want to add or delete or edit usernames of /etc/passwd in a C program. Are there any standard Linux functions that do a such functions?

I don't think that there is a standard function for it (someone correct me if I'm wrong), but you can append the information to the file. See [here](http://www.cyberciti.biz/faq/understanding-etcpasswd-file-format/) for the format. Note that you need root access to read/write to this file, and be careful when playing with it, make a backup in case something goes wrong. — Jacob H, Oct 18 '16 at 14:58

score 2 · Answer 1 · edited May 23 '17 at 10:30

2

There is adduser and deluser. Use man deluser for details.

EDIT: i missed the C part in the question.

man is also your friend in this case. With man 3 deluser you can ask if there is anything in stdlib called like that. Read https://unix.stackexchange.com/questions/3586/what-do-the-numbers-in-a-man-page-mean for more informations on that.

This is not the case. You might want to call the unix tool from within C: How do you write a C program to execute another program?

edited May 23 '17 at 10:30

Community

answered Oct 18 '16 at 15:01

dahrens

Also, `useradd`, `userdel`, `usermod`. Some distros have both these and your mentioned `adduser` and `deluser`, some have one or the other. Almost all have at least one of the sets... – twalberg Oct 18 '16 at 19:36

1 Answers1