Which command would provide you with useful information?

You are asked to determine user jack’s default login directory. Which command would provide you
with useful information?

A.
cat /etc/passwd | grep jack

B.
cat /etc/group | grep jack

C.
cat /etc/shadow | grep jack

D.
cat /etc/default/passwd | grep jack

Explanation:
The /etc/passwd contains one entry per line for each user (or user account) of the
system. All fields are separated by a colon (:) symbol. Total seven fields as follows.
1. Username: It is used when user logs in. It should be between 1 and 32 characters in length.
2. Password: An x character indicates that encrypted password is stored in /etc/shadow file.
3. User ID (UID): Each user must be assigned a user ID (UID). UID 0 (zero) is reserved for root
and UIDs 1-99 are reserved for other predefined accounts. Further UID 100-999 are reserved by
system for administrative and system accounts/groups.
4. Group ID (GID): The primary group ID (stored in /etc/group file)
5. User ID Info: The comment field. It allow you to add extra information about the users such as
user’s full name, phone number etc. This field use by finger command.
6. Home directory: The absolute path to the directory the user will be in when they log in. If this
directory does not exists then users directory becomes /
7. Command/shell: The absolute path of a command or shell (/bin/bash). Typically, this is a shell.
Please note that it does not have to be a shell.
Reference: Understanding fields in /etc/passwd