awk -F: '{ print $1 }' /etc/passwd
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Check user UID minimum on system by useradd command:
grep "^UID_MIN" /etc/login.defs
in my systemoutput is 500
Check user UID maximum on system by useradd command:
grep "^UID_MAX" /etc/login.defs
in my system output is 6000
So, we can check user list by:
awk -F':' -v "min=500" -v "max=60000" '{ if ( $3 >= min && $3 <= max ) print $0}' /etc/passwd
Example output in my virtualbox CentOS:
