My question is, is there any simple way to restart the BASH session from within the terminal on Mac. I just want the same behaviour as if I closed the terminal application and started it again (all variables reset, .bash_profile sourced etc).
I know how to source .bash_profile, but that's not what I want. One of the reasons I want to do this is because a plugin for my BASH prompt has code that prevents colors from being loaded multiple times. Therefore, sourcing .bash_profile doesn't reload the color variables and I have to restart the terminal application to get changes in effect.
Bash How To Download File From Url
Download File 🔥 https://urllio.com/2yGAmt 🔥
The accepted answer is great for a shell that's using bash, which is also what the OP asked, however, I'm using Terminal on macOS with a non-default shell (zsh) and running the command exec bash obviously doesn't have the desired effect: it launches bash instead of my default shell.
According to this article and others your shell doesn't change when you upgrade to Catalina. But any new accounts will be zsh. You can change those to bash if desired. bash will not be part of macOS at some time in the future. Apparently the licensing for zsh is less restrictive.
I find myself always needing to write shell scripts, because they can be very handy to automate tasks. Or, most importantly, because I forget the full commands to do something and I don't want to keep looking up the docs; either because the docs suck, or I'm just lazy :)
printf is used for printing and "formatting" strings, hence the f at the end. a few simple examples can be found here
The largest use-case for me is printing a new line using the new line specifier \n.
To pass a variable, you can declare it before running the script.
This is especially helpful for passing environment variables. For example: the following script expects a FRUIT and will print I Like . If FRUIT is undefined, use Apricot.
eval might not be the best choice for all cases. It is completely fine in this case since I am the only one running the script and not the end users. So exercise caution when using eval, in any programming language.
If you've reached this, then I've done something right :) I'd love to hear your feedback on the post in general. Was it organized? scattered? did it make sense? was it helpful? and what can I do to improve it?
You might want to consider replacing sh with bash if you want to actually do BASH scripting. They are different interpreters, and one can lead to vastly different set of available features depending on platform you run it on, while the other will (correctly) crash if the missing features (namely BASH) is missing on the system.
Both are definitely valid options, just if you want to write for bash then it's better to avoid ambiguity about it. When writing with support for BSD, Busybox, etc. environments in mind (e.g. inside Alpine Linux), sh is the better option, just comes with some extra baggage.
Anyway, wish I had read an article like this 9 months ago-- the information about shift, loops and functions would have gone a long way in the scripts I've been writing to provision our Ubuntu Vagrant VMs for use as localhost web dev environments.
Just as a quick comment - you should check out actual provisioning tools, such as SaltStack and Ansible if you want reproducible environments (or event driven infrastructure actions, secret management, easily distributable remote command execution, etc. etc.)
Conditions and most other such things are good to shorthand a bit, and if you're planning on using BASH use [[ ... ]] instead of [ ... ] as they also function differently. Stick to one style for predictability. serverfault.com/a/52050
I agree with you that eval, in most languages is viewed as evil. But that's largely because it might be used in applications with a lot of end users, where it is possible for something malicious to happen.
Aww thank you so much for the shout-out in the start! This looks like a great post as well, I've got it on my list to look through in more detail and take notes on the most useful scripts and commands :)
Thanks Ahmed for this concsice article covers shell scripting essentials which will help in writingand understanding the bash file...my doubt is 1. Do we need to use only the uppercase for the variable?....2. what is the difference between the sh and bash ..what is default in Mac terminal....
Using uppercase is a convention for variables from the parent environment. Lowercase for variables that are local to our script.
I see people use uppercase all the time, but it's usually just because a lot of scripts don't need local variables and that's how they learnt.
I mean, it doesn't really matter... but I am the cheerleader for Team Lowercase.
I find that I occasionally want to do tasks that Sublime Merge does not support (though I use it heavily for those that it does), or want to manipulate the git logs with command line tools. I find it minorly annoying to have to re-navigate the file tree in my shell when I already have the repo open in a program. Is it possible to launch a shell in the current repo from Sublime Merge? Specifically git-bash on Windows 10?
Aside of that, Merge can execute arbitrary git commands, so another way to go would be to do something as outlined in the below forum post. The general idea is that you set up a git alias in your global git configuration that executes some external program (in your case a git bash window that opens in a particular folder) and then create a key binding or menu entry that executes that alias.
My web server was tampered by someone who was using zsh shell. I feel more comfortable using bash shell, as that's the defaults that come with Ubuntu and OS X (the two main operating systems I use). But this questions is focused on Ubuntu server.
I have 4 websites running on this web server, I use byobu, I use tmux, I use ruby/ruby on rails, node.js, Apache, a few daemons. If I switch the current root shell from zsh to bash, could there be any negative side effects that might result from this switch? For example, will processes be killed because their parent process (the shell) has been switched?
Changing your shell, via sudo chsh --shell=/bin/bash $USER will change the shell field in /etc/passwd. This value is only consulted at login time, when the system has no idea of which shell to use for you.
Bash contains features that appear in other popular shells, and somefeatures that only appear in Bash. Some of the shells that Bash hasborrowed concepts from are the Bourne Shell (sh), the Korn Shell(ksh), and the C-shell (csh and its successor,tcsh). The following menu breaks the features up intocategories, noting which features were inspired by other shells andwhich are specific to Bash.
Bash is largely compatible with sh and incorporates usefulfeatures from the Korn shell ksh and the C shell csh.It is intended to be a conformant implementation of the IEEEPOSIX Shell and Tools portion of the IEEE POSIXspecification (IEEE Standard 1003.1).It offers functional improvements over sh for both interactive andprogramming use.
While the GNU operating system provides other shells, includinga version of csh, Bash is the default shell.Like other GNU software, Bash is quite portable. It currently runson nearly every version of Unix and a few other operating systems -independently-supported ports exist for MS-DOS, OS/2,and Windows platforms.
A Unix shell is both a command interpreter and a programminglanguage. As a command interpreter, the shell provides the userinterface to the rich set of GNU utilities. The programminglanguage features allow these utilities to be combined.Files containing commands can be created, and becomecommands themselves. These new commands have the same status assystem commands in directories such as /bin, allowing usersor groups to establish custom environments to automate their commontasks.
Shells also provide a small set of built-incommands (builtins) implementing functionality impossibleor inconvenient to obtain via separate utilities.For example, cd, break, continue, andexec cannot be implemented outside of the shell becausethey directly manipulate the shell itself.The history, getopts, kill, or pwdbuiltins, among others, could be implemented in separate utilities,but they are more convenient to use as builtin commands.All of the shell builtins are described insubsequent sections.
While executing commands is essential, most of the power (andcomplexity) of shells is due to their embedded programminglanguages. Like any high-level language, the shell providesvariables, flow control constructs, quoting, and functions.
Shells offer features geared specifically forinteractive use rather than to augment the programming language. These interactive features include job control, command lineediting, command history and aliases. Each of these features isdescribed in this manual.
Quoting is used to remove the special meaning of certaincharacters or words to the shell. Quoting can be used todisable special treatment for special characters, to preventreserved words from being recognized as such, and to preventparameter expansion.
Once you have the MO files, you decide where to install them and use theTEXTDOMAINDIR shell variable to tell the gettext tools where they are.Make sure to use the same message domain to name the MO files as you did for the PO files when you install them.
If you used that last convention, and you wanted to store the messagecatalog files with Spanish (es) and Esperanto (eo) translations into alocal directory you use for custom translation files, you could run
When all of this is done, and the message catalog files containing thecompiled translations are installed in the correct location,your users will be able to see translated stringsin any of the supported languages by setting the LANG orLC_MESSAGES environment variables before running your script.
More complex shell commands are composed of simple commands arranged togetherin a variety of ways: in a pipeline in which the output of one commandbecomes the input of a second, in a loop or conditional construct, or insome other grouping. 152ee80cbc
download pictures of artificial intelligence