Before we look into other methods, let us first understand the output of the above screenshot. The data is printed in the format shown below:<\/p>\n Let us take a closer look at what each field is for.<\/p>\n This field specifies the name of the use you want to create.<\/p>\n This field specifies the value of an encrypted password. An \u201cx\u201d in this field denotes that the encrypted password is stored in the \/etc\/shadow file.<\/p>\n This field specifies the value of the user identity number.<\/p>\n This field takes in the value of the<\/p>\n This field specifies the additional information like the full name of the user or comment (GECOS)<\/p>\n This field specifies the absolute path of the user\u2019s home directory<\/p>\n This field specifies the login shell of the user<\/p>\n 2. If you want to print out only the usernames and not the remaining data, we can either use the awk command or the cut command, let us look at both:<\/p>\n a. You can use the awk command as follows to print only the usernames:<\/p>\n b. You can use the cut command as follows to print only the usernames:<\/p>\n c. the third method to display all of the information regarding the users is using the \u201cgetent\u201d command. Use the getent command as shown below to print all the information regarding the users in the system:<\/p>\n Hopefully, by now we all know that if we want to search for something we make use of the \u201cgrep\u201d command. Similarly to check if a user exists or not, we pipe the grep command to the getent command as shown below:<\/p>\n However, we can also check if a user exists or not without the grep command also, we can simply specify the string we are searching for after the getent command as shown:<\/p>\n We also know by now that if we want to count something, we need to use the \u201cwc\u201d command. Therefore if we want to count the number of users in the passwd file, we simply pipe the getent command with the wc command along with the option \u201c-l\u201d to print out the number of lines.<\/p>\n We saw earlier that the hash passwords are stored in the file \u201c\/etc\/shadow\u201d. We can print out its contents by using the following command:<\/p>\n Before we head further, let us understand the output shown in the above screenshots. The output is in the following format:<\/p>\n Let us take a closer look at what each field is for.<\/p>\n This field specifies the name of the user<\/p>\n This field specifies the encrypted password. A black entry {::} denotes that a password is not required to login into that user\u2019s account and an asterisk, {:*:}, denotes the account has been disabled.<\/p>\n This field gives information about when the password was last changed<\/p>\n This file specifies the number of days after which the password will expire<\/p>\n The warning period specifies the number of days before the password expiry date, from which the user will start receiving a warning notification for password change.<\/p>\n The account validity field specifies the number of days after which the account will be disabled, once the password is expired<\/p>\n The account disability field specifies the number of days since which the account had been disabled.<\/p>\n Now that we know how to list all the users in the system, let us discuss the types of users in an operating system. Generally speaking, there are 2 types of users in Linux:<\/p>\n The system user is the one that creates normal users. In other words, the system user is the root. The system user is automatically created when you first install the operating system. Moreover, you can also create system users for particular applications and programs.<\/p>\n The normal users are the ones that are created by the system or root user, actually, we even users with sudo privileges can create normal users<\/p>\n We saw earlier how the user identification number is allotted to each user, If you want to check what the UID range is for the normal users, use the following command:<\/p>\n Now that we have the UID range of the normal user, we can use this to print all the normal users in the system by using the following command:<\/p>\n Just before we finish, here is a bonus method for printing the user information – using the cat command. Just like the gentent command, we use the following command:<\/p>\n As you have seen, listing users can be done by many commands like cut, cat, awk, getent, and many more. You have now learned what users are, what happens when we create them, and different ways to list the users using various commands like awk, cut, cat and getent.<\/p>\n You have also learned some bonus commands like displaying the number of users, UID range, printing only the usernames, searching for a particular user name, printing only normal users, and more. Apart from all of this, you also understood the format of the output that is printed on the screen.<\/p>\n","protected":false},"excerpt":{"rendered":" In this article, you will learn how to list the users in Linux-based operating systems. We will learn more about users, what happens when we create them and then will we see how to...<\/p>\n","protected":false},"author":1,"featured_media":110812,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[35],"tags":[27096,27097],"class_list":["post-110804","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-linux","tag-how-to-list-users-in-linux","tag-listing-users-in-linux"],"yoast_head":"\n![\"listing](\"https:\/\/data-flair.training\/blogs\/wp-content\/uploads\/sites\/2\/2022\/08\/listing-all-the-users-in-the-passwd-file-by-using-the-less-command.webp\")
<\/a><\/p>\n<username>:<password>:<UID>:<GID>:<GECOS>:<home_dir>:<shell_path><\/pre>\n
a. <username><\/h4>\n
b. <password><\/h4>\n
c. <UID><\/h4>\n
d. <GID><\/h4>\n
e. <GECOS><\/h4>\n
f. <home_dir><\/h4>\n
g. <shell_path><\/h4>\n
awk -F: \u2018{ print $1 }\u2019 \/etc passwd<\/pre>\n<\/a><\/p>\ncut -d: -f1 \/etc\/passwd<\/pre>\n
<\/a><\/p>\ngetent passwd<\/pre>\n
<\/a><\/h3>\nChecking if a user exists or not<\/h3>\n
<\/a><\/p>\ngetent passwd <username><\/pre>\n
<\/a><\/h3>\nCounting the number of users<\/h3>\n
<\/a><\/p>\nPrinting the contents of the \/etc\/shadow file<\/h3>\n
less \/etc\/shadow<\/pre>\n
<\/a><\/p>\n[username]:[enc_pwd]:[last_pwd_change]:[pwd_validity]:[warn_date]:[acc_validity]:[acc_disablity]<\/pre>\n
1. [username]<\/h4>\n
2. [enc_pwd]<\/h4>\n
3. [last_pwd_change]<\/h4>\n
4. [pwd_validity]<\/h4>\n
5. [warn_date]<\/h4>\n
6. [acc_validity]<\/h4>\n
7. [acc_disablity]<\/h4>\n
Types of users in Linux<\/h3>\n
1. System user<\/h4>\n
2. Normal user<\/h4>\n
Checking UID_MINand UID_MAX<\/h3>\n
grep -E '^UID_MIN|^UID_MAX' \/etc\/login.defs<\/pre>\n
<\/a><\/h3>\nListing normal users only<\/h3>\n
getent passwd {1000..6000}<\/pre>\n<\/a><\/h3>\nUsing the cat command to list users<\/h3>\n
cat \/etc\/passwd<\/pre>\n
<\/a><\/h3>\nSummary<\/h3>\n