"users" command would be the best choice as it only outputs the usernames without extra useless text.
Username may contain a dot that requires extra handling in regular expression, so I think use a loop to compare the string is easier than using grep.
Code:
#!/bin/bash
user="$1"
found=0
for i in `users`; do
if [ "$i" == "$user" ]; then
found=1
break
fi
done
if [ "$found" -eq 1 ]; then
echo "User logged in."
else
echo "User not logged in."
fi
This User Gave Thanks to MacMonster For This Post:
Hi
I am using mailx to send email and am wondering if there is a way I can send the email from a different user than the user logged in.
something like do-not-reply@xyz.com
Thank you. (1 Reply)
I have 2 systems. (1) RHEL5 and (2) winXP pro
from xpPRO putty i ssh into rhel5 : user root
from xpPRO i ftp into rhel5 : user abc123
when i run #uptime it only shows 1 user
when i do #ps -u abc123 : it shows vsftpd deamon PID
is there a command that can be used to show all currently... (4 Replies)
Ok, so, in order to install some dependencies of a program I made, a script has to be run as root. The thing is that I have to copy some things into the home folder of currently logged in user, but the variable $HOME returns '/root' and the $USER returns 'root' :(
Is there any way to see who is... (7 Replies)
Hi, first time poster, newbie to Bash. I'm looking to get the username of the user who's been logged into a computer the most / longest.
I am new to Bash but am familiar with other scripting languages, mainly PHP. So I have a general idea about how to go about the script logic, but don't know... (13 Replies)
How do I confirm if a user logged in, is remote or local? In the case if the user is remote, how to be sure what authentication/method is it using, like LDAP, NIS or other? (2 Replies)
hi!
How can I find into:
/var/log/messages.4
/var/log/messages.3
/var/log/messages.2
/var/log/messages.1
/var/log/messages
The last user do a login? (for example user1)
My idea is to search by the pattern "Accepted password for" buy I necessary search into all files first and in the... (2 Replies)
1. The problem statement, all variables and given/known data:
Show all users who are currently logged in, sorted from earliest to latest log in time. The log in time includes the month, day, and time.
2. Relevant commands, code, scripts, algorithms:
finger, who, sort, pipe, head, tail,
... (8 Replies)
Discussion started by: vtmd
8 Replies
LEARN ABOUT PHP
stristr
STRISTR(3) 1 STRISTR(3)stristr - Case-insensitivestrstr(3)SYNOPSIS
string stristr (string $haystack, mixed $needle, [bool $before_needle = false])
DESCRIPTION
Returns all of $haystack starting from and including the first occurrence of $needle to the end.
PARAMETERS
o $haystack
- The string to search in
o $needle
- If $needle is not a string, it is converted to an integer and applied as the ordinal value of a character.
o $before_needle
- If TRUE, stristr(3) returns the part of the $haystack before the first occurrence of the $needle (excluding needle).
$needle and $haystack are examined in a case-insensitive manner.
RETURN VALUES
Returns the matched substring. If $needle is not found, returns FALSE.
CHANGELOG
+--------+-----------------------------------------------+
|Version | |
| | |
| | Description |
| | |
+--------+-----------------------------------------------+
| 5.3.0 | |
| | |
| | Added the optional parameter $before_needle. |
| | |
| 4.3.0 | |
| | |
| | stristr(3) was made binary safe. |
| | |
+--------+-----------------------------------------------+
EXAMPLES
Example #1
stristr(3) example
<?php
$email = 'USER@EXAMPLE.com';
echo stristr($email, 'e'); // outputs ER@EXAMPLE.com
echo stristr($email, 'e', true); // As of PHP 5.3.0, outputs US
?>
Example #2
Testing if a string is found or not
<?php
$string = 'Hello World!';
if(stristr($string, 'earth') === FALSE) {
echo '"earth" not found in string';
}
// outputs: "earth" not found in string
?>
Example #3
Using a non "string" needle
<?php
$string = 'APPLE';
echo stristr($string, 97); // 97 = lowercase a
// outputs: APPLE
?>
NOTES
Note
This function is binary-safe.
SEE ALSO strstr(3), strrchr(3), stripos(3), strpbrk(3), preg_match(3).
PHP Documentation Group STRISTR(3)