Invoking a program by using it’s Path You can execute programs by typing out the full path name and the program name at the terminal prompt: $ /bin/ls Or you can just type the program name: $ ls As long
Linux OS Directories
/bin /usr/bin Contains programs available to all users /sbin /usr/sbin Contains programs meant to be used by system administrators /var/log Contains the log files made by various applications. /home Contains all the personal directories of the users of the system
Linux System Devices Mounting and Unmounting
Devices on the system Every device on the Linux system is represented by a file in the /dev directory /dev/fd0 The first floppy drive in the computer /dev/hda The first master IDE Hard Disk Drive /dev/dsp The first audio DSP
Searching for Files in Linux
There are two different programs that enable us to search the Linux file system. Locate This program works by building a daily database of files and their respective locations. When a search is performed, it looks in the DB for
Linux CPU Information and Commands
The CPU information detected by the OS can be found by displaying the contents of the file /proc/cpuinfo $ cat /proc/cpuinfo The bogomips value given at the bottom of the file is a rough calculation of the CPUs speed, made
Linux terminal commands found in /bin directory
Command Description awk Pattern scanning and processing language bash The Bourne again Shell cat Concatenates files and prints onto standard output chgrp Changes the group ownership chmod Changes file access permissions chown Changes file ownership permissions cp Copies files and
Linux terminal commands found in /etc directory
Command Description exports Lists the file systems to be exported by NFS ftpaccess Configuration file for ftpd group Lists the various groups on the system and each of their members hosts Lists the hostname and IP addresses of machines host.conf
Linux commands found in /sbin
Command Description arp Prints the ARP table of a machine cardmgr PCMIA devices manager chkconfig Manages runlevel information for system devices debugfs Ext2 File System debugging utility dhclient DHCP Client e2fsck Ext File system diagnosis and repair tool fdisk Disk
Linux commands found in /usr/bin
Command Description at Queue jobs for later execution bc A bench calculator cc C-compiler. Symbolic link to GNU C Compiler clear Clears the screen crontab Maintains a list of tasks to be performed later du Reports disk usage for a
Linux terminal commands found in usr/sbin/
Command Description adduser Creates a new user automount Configures mount points for autofs chpasswd Updates password file in batch mode chroot Runs command with the root set to a new root gpm Mouse based cut and paste utility for virtual