Difference between revisions of "Other standard shells"

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==Find out available binary packages shell list==
 
==Find out available binary packages shell list==
 
To find the list of available shell packages under [[Red Hat Enterprise Linux]] / [[CentOS Linux]] / [[Fedora Linux]], enter:
 
To find the list of available shell packages under [[Red Hat Enterprise Linux]] / [[CentOS Linux]] / [[Fedora Linux]], enter:
<source lang="bash">yum search shell</source>
+
<syntaxhighlight lang="bash" >yum search shell</syntaxhighlight>
  
 
To find the list of available shell packages under [[Debian Linux]] / [[Ubuntu Linux]], enter:
 
To find the list of available shell packages under [[Debian Linux]] / [[Ubuntu Linux]], enter:
<source lang="bash">apt-cache search shell</source>
+
<syntaxhighlight lang="bash" >apt-cache search shell</syntaxhighlight>
 
==Pathnames of valid login shells==
 
==Pathnames of valid login shells==
 
[[/etc/shells]] is a text file which contains the full pathnames of valid login shells.  This file is consulted by chsh and available to be queried by other programs such as ftp servers.
 
[[/etc/shells]] is a text file which contains the full pathnames of valid login shells.  This file is consulted by chsh and available to be queried by other programs such as ftp servers.
<source lang="bash">cat /etc/shells</source>
+
<syntaxhighlight lang="bash" >cat /etc/shells</syntaxhighlight>
 
Sample outputs:
 
Sample outputs:
 
<pre>/bin/sh
 
<pre>/bin/sh
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===which command===
 
===which command===
 
You can also use the [[which command]] to display the full path of (shell) commands:
 
You can also use the [[which command]] to display the full path of (shell) commands:
<source lang="bash">which commandname
+
<syntaxhighlight lang="bash" >which commandname
which bash</source>
+
which bash</syntaxhighlight>
 
Sample outputs:
 
Sample outputs:
 
<pre>/bin/bash</pre>
 
<pre>/bin/bash</pre>
 
For each of its command line arguments it prints to [[stdout]] (screen) the full path of the executables that would have been executed when this argument had been entered at the shell prompt:
 
For each of its command line arguments it prints to [[stdout]] (screen) the full path of the executables that would have been executed when this argument had been entered at the shell prompt:
<source lang="bash">
+
<syntaxhighlight lang="bash" >
 
which date
 
which date
 
which gcc
 
which gcc
which vi</source>
+
which vi</syntaxhighlight>
[[Category:Introduction to Shells]]
+
 
 +
However, which cannot tell you exactly what the shell will execute in all cases as it is an external command. For more accurate information, use [[type command]] as follows:
 +
<syntaxhighlight lang="bash" >type -p commandName
 +
type -p bash
 +
type -p date
 +
type -p gcc
 +
type -p echo
 +
</syntaxhighlight>
 +
[[Category:Introduction to Shells]][[Category:Commands]]
 +
 
 +
{{navigation
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|previous=The role of shells in the Linux environment
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|next=Hello, World! Tutorial|Write a simple shell script - "Hello World!"}}

Latest revision as of 22:50, 29 March 2016

← The role of shells in the Linux environmentHomeHello, World! Tutorial →

In Linux, a lot of work is done using a command line shell. Linux comes preinstalled with Bash. Many other shells are available under Linux:

  • tcsh - An enhanced version of csh, the C shell.
  • ksh - The real, AT&T version of the Korn shell.
  • csh - Shell with C-like syntax, standard login shell on BSD systems.
  • zsh - A powerful interactive shell.
  • scsh- An open-source Unix shell embedded within Scheme programming language.

Find out available binary packages shell list

To find the list of available shell packages under Red Hat Enterprise Linux / CentOS Linux / Fedora Linux, enter:

yum search shell

To find the list of available shell packages under Debian Linux / Ubuntu Linux, enter:

apt-cache search shell

Pathnames of valid login shells

/etc/shells is a text file which contains the full pathnames of valid login shells. This file is consulted by chsh and available to be queried by other programs such as ftp servers.

cat /etc/shells

Sample outputs:

/bin/sh
/bin/bash
/sbin/nologin
/bin/tcsh
/bin/csh
/bin/zsh
/bin/ksh

which command

You can also use the which command to display the full path of (shell) commands:

which commandname
which bash

Sample outputs:

/bin/bash

For each of its command line arguments it prints to stdout (screen) the full path of the executables that would have been executed when this argument had been entered at the shell prompt:

which date
which gcc
which vi

However, which cannot tell you exactly what the shell will execute in all cases as it is an external command. For more accurate information, use type command as follows:

type -p commandName
type -p bash
type -p date
type -p gcc
type -p echo

← The role of shells in the Linux environmentHomeHello, World! Tutorial →