07-30-2013
Significance of different shells?
I'm taking a LINUX and UNIX class and we are using bash as the shell in terminal. On my mac-book I use zsh only because my professor had a pretty cool start-up file for it.
It has benefited me in becoming familiar with different shells. However, I'm having a hard time understanding the purpose of the shell and why there are so many shells out there and the importance or instance of using one over the other.
I understand zsh is very powerful. However, I see the same with bash. I wrote a few simple scripts in bash as well as zsh and see that they are very familiar in syntax. I've also found out that it doesn't matter what shell I'm in when I want to run a script.
For example, #!/bin/bash, stating this in the top of my bash script still allows me to run it in zsh.
It also seems that no matter what shell your currently in the commands at the command line are always the same as far as navigating around.
Therefore, what's the purpose of the shell and instances/advantages of using one over the over?
Last edited by syregnar86; 07-30-2013 at 04:59 PM..
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LEARN ABOUT DEBIAN
surfraw-update-path
SURFRAW-UPDATE-PATH(1) User Contributed Perl Documentation SURFRAW-UPDATE-PATH(1)
NAME
surfraw-update-path - updates PATH in shell config files
SYNOPSIS
surfraw-update-path [-add] [-remove] [-check] [-sys] [-all] [-help] [-shell=SHELL]
DESCRIPTION
surfraw-update-path adds the surfraw elvi directory (/usr/lib/surfraw) to your PATH in your shell's config file.
Currently it supports bash, sh, csh, tcsh, ash, dash, ksh, pdksh, zsh, rc, and es
Don't forget to login again or source your login files for it to take effect.
OPTIONS
-check
Checks to see if the surfraw config code is present. This is the default.
-add
Adds the surfraw config code.
-remove
Removes the surfraw config code
-sys
Updates the system-wide shell config instead of the user. Must be done as root.
-shell=SHELL
Selects the shell to configure. Defaults to the value of the $SHELL environment variable.
Currently supported shells are:
sh, ash, bash, dash, csh, tcsh, ksh, pdksh, zsh, rc, and es.
-all
Attempts to configure the startup files for all known shells
-help
Gives a usage message
RETURN VALUE
-check returns 0 if the surfraw code is present in the file, 1 if it is not found, or 2 on error.
All other options return 0 on success, or 2 on error.
ENVIRONMENT
SHELL
Used to determine which shell to configure, if -shell is not given.
HOME
Used to find users config files.
ENV Used by posix-compliant shells to specify a startup rc file.
ZDOTDIR
Used to find user config files for zsh. If not set, defaults to HOME.
SEE ALSO
surfraw(1), sh(1), ash(1), bash(1), dash(1), csh(1), tcsh(1), ksh(1), pdksh(1), zsh(1), rc(1), es(1)
AUTHOR
Ian Beckwith <ianb@erislabs.net>
perl v5.12.4 2011-07-12 SURFRAW-UPDATE-PATH(1)