The ftp command in Linux connects to a remote FTP server and transfers files. FTP transmits everything in plain text: credentials and…
The lsmod command in Linux lists all currently loaded kernel modules. It reads /proc/modules — a virtual file maintained by the kernel — and…
The rename command in Linux renames multiple files at once using Perl regular expressions. Unlike mv, which handles one file at a time, rename applies…
The pgrep command in Linux finds the PIDs of running processes based on a name or other criteria. It is part of…
The unlink command in Linux removes a single file by deleting its directory entry. It is a thin wrapper around the unlink() POSIX system…
When troubleshooting a network connection or configuring a firewall, the first question is whether a port is actually reachable. This…
The ifconfig command in Linux displays and configures network interfaces. It can assign IP addresses, bring interfaces up or down, change MTU…
The groupdel command in Linux removes a group from the system. It deletes the group's entry from /etc/group and /etc/gshadow, but does not delete or…
The wc command in Linux counts lines, words, characters, and bytes in files or standard input. It is most useful in shell…
The top command in Linux provides a real-time view of running processes and system resource usage. From a single interactive screen you…