Folders: - /sbin/ = Linux discriminates between 'normal' executables and those used for system maintenance and/or administrative tasks. The latter reside in '/sbin' or - the less important ones - in '/usr/sbin'. - /usr/sbin/= System administrative programs. - /usr/local/sbin/ = Locally installed system administration programs - /etc/ = Contains system configuration files such as psswd, hosts, shodow, fstab Files: - ~/.bash_profile = User's personal configuration file for login shells. Here you write the PATH variable Ex: # User specific environment and startup programs PATH=$PATH:$HOME/bin PATH=$PATH:/usr/sbin:/sbin PS1="[\u@\w] > " - /etc/bashrc = global configuration file. Ex: # System wide functions and aliases alias lls='ls -lh' ************************************** - /etc/fstab = is a configuration file that contains information of all the partitions and storage devices in your computer. The first column contains the device name, the second one its mount point, third its filesystem type, fourth the mount options, fifth (a number) dump options, and sixth (another number) filesystem check options. Link: ../netLinux/fstab.html Exemplu: /dev/hda1 /mnt/windows ntfs ro,defaults,umask=0222 0 0 /dev/hda5 /mnt/vfat vfat uid=daniel,umask=017 0 0 ********************* - /boot/vmliuz* = where linux kernel is located - /etc/passwd = This file holds the majority of information about accounts on the Unix system - /etc/shells = is a text file which contains the full pathnames of valid login shells Environment Variables - PS1 = controls the top-level command prompt, or string of characters before the cursur - PATH = contains a list of directories where executables files might be located ---------------------------------------------------------------------- - PS1 = controls the top-level command prompt, or string of characters before the cursur Exemplu: PS1="[\u \w] > " Escape_Sequence = Function \t = Current time, expressed as HH:MM:SS. \d = Current date, expressed as Weekday Month Date (or Day). \n = Newline. \s = Current shell environment. \W = Working directory. \w = Full path of the working directory. \u = Current username. \h = Hostname of the current machine. \# = Command number of the current command. Increases with each new command entered. \$ = If the effective UID is 0 (that is, if you are logged in as root), end the prompt with the # character; otherwise, use the $. ---------------------------------------------------------------------- - PATH = contains a list of directories where executables files might be located The value of the PATH variable is usually set in a configuration file such as '/etc/profile'. You can add your own values to the PATH variable. PATH=$PATH:new_value Exemple: PATH=$PATH:/usr/sbin/ Multiple directories can be added as a colon-separated list ('director1:director2'). The user can add the command export PATH -> the new value of the variable will be available outside of that particular iteration of the shell The $ sign at the beginning of the PATH statement tells the shell that the new directory is to be appended to the current value of PATH rather than replacing it.