Several popular shell
At present, popular shells have ASH, BASH, KSH, CSH, ZSH, etc. You can view your own shell type with the following command: # echo $ shell $ shell is an environment variable, which records the shell type used by the user. You can use the command: # shell-name to convert to other shells, here shell-name is the name of the shell you want to try, such as ASH, etc. This command starts a shell again, this shell is after the SHELL that is originally logged in, called the subordinate shell or sub-shell Using the command: # EXIT can exit this child shell. The reason for using different shells is that they have their own characteristics, and they will be a simple introduction: 1. Ashash Shell is written by Kenneth Almquist, which is a small shell that takes up the least system resources in Linux. It only contains 24 internal commands, so it is very inconvenient. 2. Bashbash is the default shell of the Linux system, which is completed by Brian Fox and Chet Ramey, which is the abbreviation of the Bourne Again shell, and there are 40 internal commands. Linux uses it as the default shell because it has the following features: (1) You can use the DOSKEY of the DOS, use the up and down direction to check and quickly enter and modify the command. (2) Automatically gives a command that starts with a string by finding a match. (3) Contains its own help function, you can get relevant help as long as you type HELP below the prompt. 3. Kshksh is an abbreviation of Korn Shell, written by Eric Gisin, a total of 42 internal commands. The biggest advantage of the shell is that almost the KSH of the commercial release is completely compatible, so you can try the performance version of the business version without spending a business version. 4. CSH CSH is a relatively large core of Linux, which is compiled by 47 authors represented by William Joy, with a total of 52 internal commands. The shell actually points to a shell such as / bin / tcsh, that is, the CSH is actually TCSH. 5. ZCH ZCH is one of the largest shells of Linux, completed by Paul Falstad, with a total of 84 internal commands. If it is just a general purpose, it is not necessary to install such a shell.
