Types of Shell
UNIX system command is a program that Performs a desired function. UNIX command programs are either simple Utilities that perform simple operations or Complex interactive programs.
The shell program interprets the commands we type.
Shell prompts
$ - Bourne shell
% - C shell
# - Super User
There are many shells (interpreters) available on UNIX. There are 3 widely used shells namely:
Bourne shell (sh), C Shell (csh) and Korn Shell or K-Shell (ksh)
Bash shell is a super set of all the shells. Each and every Unix flavour consists of above three shells.
Features | Bourne Shell (sh) | Korn shell (ksh) | C shell (csh) | Bash Shell (bash) |
---|---|---|---|---|
Alias | No | Yes | Yes | Yes |
History (doskey like dos) | No | Yes | Yes | Yes |
profile | .profile | .profile | .login | .bash_profile |
Logout | - | .logout | .logout | .bash_logout |
History file | - | .sh_history | .history | .bash_history |
Variable declaration | a=10 | a=10 | a 10 | a=10 |