CharlesDuffy correct, and it was available when I wrote this - however, it's still not default behaviour - you need bash 4. Shopt options are awkward, as their setting can actually trigger syntax errors. Kristian Kristian 2 2 bronze badges. HP-UX provides sh, csh, and ksh as default shells. In But, given the amount of That's how I have mine set. Jon Ericson Jon Ericson For one thing, bash has tab completion.
This alone is enough to make me prefer it over ksh. Allen Allen 4, 21 21 silver badges 30 30 bronze badges. Source: kornshell. Hank Gay Hank Gay This takes a lot of people by surpise when their "valid" bash commands are rejected by! Incident Incident 4 4 silver badges 7 7 bronze badges. As of this answer's writing, ksh93 arguably had more bells and whistles from a programming perspective associative arrays and namevars come first to mind -- though that's changed in the intervening eight years.
It still has floating-point math, which bash continues to lack. MeaCulpa MeaCulpa 6 6 silver badges 14 14 bronze badges. I can not really address the actual programming differences between the shells, unfortunately.
If you are planning to distribute scripts use posix-sh. Bash is a good shell, and the default on linux. Older Unix flavors tend to have sh, ksh, and csh. In a production environment, it can be difficult to get permission or forgiveness for installing the shell of your choice on all the systems. Even when you tell it specifically not to, it usually lets you anyway. The vi mode in Bash is also pretty poorly implemented.
Matthieu Matthieu 5 5 silver badges 8 8 bronze badges. I'd say bash is a standard. The original Bourne shell sh is the standard for cross-platform scripts. Posix-sh is or perhaps 'should be' the standard for cross platform scripting. Corrected: Bash is the standard for Linux. The Overflow Blog.
Does ES6 make JavaScript frameworks obsolete? Podcast Do polyglots have an edge when it comes to mastering programming Featured on Meta. Now live: A fully responsive profile. Linked The above description clearly explains what the Korn shell and Bash are and the major differences between the two. Both are decent shells and function as interactive command interpreters. Both share almost the common features so these can be used interchangeably. Both the shells are standard shells, so it depends on the choice and need of the programmer to use them according to the requirements.
This is a guide to Korn Shell vs Bash. Here we also discuss the Korn Shell vs Bash key differences with infographics and comparison table. You may also have a look at the following articles to learn more —. Submit Next Question. By signing up, you agree to our Terms of Use and Privacy Policy. Forgot Password? Wildcards and shortcuts. Once again, your personal productivity and general peace of mind will be enhanced by a shell that provides you with fast ways to do common things.
Wildcards, command aliases, and completion can save you a great deal of typing if you enter many UNIX commands in the course of a day. If you sit in front of the same terminal every day, use the same UNIX software and applications for all your work, and rarely, if ever, deal with an unfamiliar system, then, by all means, choose the best tools that your system has available. If you need to work with many different computers running different versions of UNIX, as system and network administrators often must, you may need to build a repertoire of tools shell, editor, and so on that are available on most or all of the systems you use.
Don't forget that being expert with a powerful shell won't buy you much if that shell isn't available. Table Ranking of shells for interactive use. If you won't be spending a lot of time using a command shell with UNIX, then, by all means, develop some proficiency with the Bourne shell.
You'll be able to do all you need to, and the productivity benefits of the other shells aren't important for a casual user. Even if you expect to use a UNIX command shell frequently, you might need to limit your study to the Bourne shell if you need to become effective quickly.
I rated the Bourne shell as lowest in the productivity categories because it has no command editor and only minimal shortcut facilities. If you have the time and expertise to invest in developing your own shell scripts, you can compensate for many of the Bourne shell deficiencies, as many shell power users did in the years before other shells were invented.
Even so, the lack of command editing and command history facilities means you'll spend a lot of time retyping and repairing commands. For intensive keyboard use, the Bourne shell is the worst of the three. If you have any other shell, you'll prefer it over the Bourne shell. Shells like the C shell and the Korn shell were invented precisely because of the Bourne shell's low productivity rating. The new shells were targeted specifically to creating a keyboard environment that would be friendlier and easier to use than the Bourne shell, and they are here today only because most people agree that they're better.
Portability concerns, however, might steer you toward the Bourne shell despite its poor productivity rating. Being the oldest of the three shells it was written for the very earliest versions of UNIX , the Bourne shell is available virtually everywhere. If you can get your job done using the Bourne shell, you can do it at the terminal of virtually any machine anywhere.
This is not the case for shells such as the C and Korn shells, which are available only with particular vendors' systems or with current UNIX releases. I gave the Bourne shell a rating of 3 for prior experience because prior experience using the Bourne shell is no reason to continue using it.
You can immediately use any of Bourne shell variants, such as the Korn or Bourne Again shell, with no additional study and no surprises, and you can gradually enhance your keyboard skills as you pick up the new shell extensions. If you know the Bourne shell and have access to a Bourne shell variant, you have no reason not to use a variant. For example, on HP-UX The POSIX shell is very similar to the Korn shell in terms of the interactive features provided, right down to the keystroke in most cases.
The Korn shell is not standardized, so there are annoying differences between various vendor's versions; the POSIX shell attempts to raise the bar for a universally available shell. The POSIX shell rates a 1 in the area of command editing, providing both vi and emacs command support. The POSIX shell offers many shortcuts, such as aliases, cd path searches, filename completion and job control.
The POSIX shell rated a 2 in the experience category, because if you know the POSIX shell and are satisfied with its feature set, there isn't a large set of compelling reasons to switch to another shell. The Bourne Again and Z shells offer more features, and support most of the POSIX features, so if default availability is not an issue and you need the extra features, switching should be a fairly painless task.
C Shell The C shell rates a 2 for learning difficulty, based simply on the total amount of material available to learn. The C shell falls on the low end of the shell spectrum in terms of the number and complexity of its facilities. Make no mistake--the C shell can be tricky to use, and some of its features are rather poorly documented. Becoming comfortable and proficient with the C shell takes time, practice, and a certain amount of inventive experimentation.
When compared to the Bourne shell only on the basis of common features, the C shell is no more complex, just different. The C shell rates a passing nod for command editing because it doesn't really have a command editing feature.
The C shell's history substitution mechanism is somewhat complicated to learn and can be clumsy to use at times, but it is much better than nothing at all. Just having a command history and history substitution mechanism is an improvement over the Bourne shell.
For example, with the Korn shell, you can reuse a previously entered command, even modify it, just by recalling it Esc-k if you're using the vi option and overtyping the part you want to modify. With the C shell, you can also reuse a previous command, but you have five different forms for specifying the command name!! Even remembering the syntax of command substitution is difficult, not to mention using it.
The history substitution mechanism also provides no access to multi-line commands such as foreach. The lack of access to multi-line commands can be frustrating; you have to retype all the enclosed commands.
History substitutions, once you have learned the syntax, can be much faster than editing in many cases, because fewer keystrokes are required. However, there is no substitute for a good command-line editor.
On the other hand, if you like to use wildcards, you'll find that the C shell wildcard extensions for filenames are easier to use--they require less typing and have a simpler syntax--than the Korn shell wildcard extensions.
In addition to wildcards, csh provides command and filename completion with a single keystroke. Also, its cd command is a little more flexible. The pushd , popd , and dirs commands are not directly supported by some shells, such as the Korn and POSIX shells although they can be implemented in those shells by the use of aliases and command functions. Altogether, the C shell rates well in terms of keyboard shortcuts available, perhaps in compensation for its only moderately successful command editing.
Depending on your personal mental bent, you might find the C shell very productive. We have seen that those already familiar with the C shell have in the past not been driven away in droves by the Korn and other shells.
For portability considerations, the C shell ranks at the bottom, simply because it's a unique shell language. If you know only the C shell, and the particular system you're using doesn't have it, you're out of luck.
A C shell user almost always feels all thumbs when forced to work with the Bourne shell, unless she is bilingual and knows the vagaries and peculiarities of both. The C shell gets a 2 for prior experience. If you already know the C shell, the TC shell is a good candidate for a switch. The TC shell provides a command-line editor and other nifty shortcuts and is probably compatible with your current C shell version. On the other hand, staying with a C shell variant can be limiting because there are many more shells in the Bourne family tree.
Unless you feel quite comfortable with the C shell's history substitution feature and use it extensively to repair and reuse commands, you might find another shell's command editing capability well worth the time and effort to make a switch. Anyone accustomed to using the shell's command editing capability feels unfairly treated when deprived of it--it's that good of a feature.
Because it echoes some of the features of the original Bourne shell, it also has features similar to those of the Korn shell, with some added extensions. The Bash, compared to the KSH shell, is more recent, more popular, and has a multitude of resources for people who wish to learn about using this particular shell. Two of the useful features of Bash are tab completion and the easier method of setting a prompt in order to display the current directory.
Bash is also the current default shell in many Linux models. Both shells can be used interchangeably since they share some features of the Bourne shell. A syntax in the KSH shell can run in a Bash shell without encountering errors or problems. Bash and KSH are both Bourne-compatible shells. Since they share common features, they can be used interchangeably.
This causes some confusion for novice users. Both KSH and Bash are available to use in many platforms. Bash is a newer shell compared to the KSH.
Bash, as the newer shell, has more resources and more computer users. Bash is a free and public utility shell that is often used in open-source communities and applications. Bash also acts as an extension of the Korn shell, since it incorporates the features of the latter, with some added features. Cite APA 7 Franscisco,.
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