But just using python can be a bit tough without the help of bash shell scripting. So, let us write a python program to do the same Now, this file first reads the input from the sys.
All the output is written to the sys. After creating this script, assuming that you have named it as order. Now we have seen how we can combine python and shell scripts to create a chain of commands and execute them together.
Speaking of bash shell programming, in terms of performance, bash totally beats the crap out of python. The start-up time of a bash shell script is 2. To be franker, bash is a general-purpose language just like Python, but both have their own strengths and weaknesses. Bash shell programming is the default terminal in most Linux distributions, and thus it will always be faster in terms of performance.
But does that mean it can totally replace Python? When dealing with large programs, Bash will keep on getting complicated, whereas Python does not. Python can also be used as an Object-oriented language, as far as I know. If you are just a beginner, then you might not even know the difference between the two. Python is the most elegant scripting language, even more than Ruby and Perl. On the other hand, Bash shell programming is actually very excellent in piping out the output of one command into another.
The real power of shell scripting lies in the Stream Text editor or sed, the Awk Programs and similar apps. Bash Shell Scripting works flawlessly and fast when dealing with files.
By handling files, I mean copying, cloning disks, writing backup apps for networking, ftp servers , storing file inputs and accessing them later and transferring those outputs later on to something else with the help of a pipe. On the other hand, Python is more useful for dealing with chunks of data such as reading data from a file and processing data. If I be more specific, bash is not even a programming language. Thus, if you know bash shell programming properly, you also know that variables and scopes in bash are extremely limited.
Heise writes an introduction to bash programming in german :. Bash is not a fully featured programming language at all, and nothing in bash is ever easy. You are advised to use a proper programming language early on in development, and if possible never put bash commands into a file. Bash is also bad at safely handling filenames with weird characters in them, bad at handling Unicode, bad at handling Errors and bad at many other elementary things.
Basically, it is better to start in something else right away if the things move away from an interactive command line and end up in a file. Use whatever you like as an interactive command line, but do not write bash or shell scripts. Shell is a thing you want to understand and then not use, because you learned to understand it. Use the system Python, if possible, but do not try to modify the system Python installation. Use a virtual environment for packages, instead.
This will create a local symlinked copy of the system python, and activate it as the interpreter environment to modify if you install dependencies. You will want to update pip , install wheel and then maintain a file named requirements.
It will contain the names of the packages optionally with version pins you depend on. You can install the dependencies using pip install -r requirements. It deactivates the venv, throws away the installed venv, and then re-makes it from the requirements.
Running a local Python package registry is as simple as exposing a directory with a specific file structure using a web server, see here , and a step-by-step walkthrough for a kind of minimal setup can be found here. In an online discussion, somebody remarked :. The point here is that this is not useful at all, in a Python program. Talk like Gollum all through the movie. At the end, bite off someone's finger and fall down the stairs.
When Shelob appears, pinch the guy in front of you on the back of the neck. When Denethor lights the fire, shout "Barbecue! Every time someone kills an Orc, yell: "That's what I'm Tolkien about! Python is a programming language. You use it and other programming languages to do things that you would not otherwise accomplish by entering commands at a shell prompt. Its not exactly apples to apples comparison, so it depends. I would prefer Bash for quick and small scripts over Python.
Probably python, definitely for anything longer than few lines. There are also some nifty CLI tools be it git or skopeo which can be accessed from python see subprocess. Popen , shlex if they don't have equivalent Requests.
On higher level Ansible comes to play To the fact, bash is a lot slower than python. GNU Bash being native Linux tool was simply designed to perform regular administrative tasks, some of us does use it for a lot other things, which is good to some extent. Bash is slower except for the startup time compare to Python, but anyway the difference is so tiny to find a human noticeable difference.
They complete each other. I write lots of small bash scripts on linux, like I do powershell on windows. I then run them through a modified subprocess and return response in json. All the ductape holding it together like auth, web, ssh, https etc is python. Bash is also very os centric and relies heavily on linux commands. Do you have any data or proof that bash is slower? The overhead of setting up python, the fact that it breaks terribly between versions..
Its dependency hell and so many other cons are not mentioned. It's a rather biased opinion.
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