I am on Windows.
I have a script file named basics.sh and here is what it contains:
cd opt-out-exam/abduvosid_malikov/IT
mkdir made_by_my_script
cd made_by_my_script
echo "Hello World" > hello.txt
so basically, basics.sh script file is responsible to:
go to folder opt-out-exam/abduvosid_malikov/IT
make a directory made_by_my_script
create hello.txt file with content Hello World
Right now. to execute this basics.sh script, I am going to IT folder and writing this command in the terminal:
./basics.sh
In order to execute this basics.sh script, is it compulsory for me to go to IT folder
OR
is it possible to execute this script file even if I am staying in another folder (lets say currently working directory is opt-out-exam)
The first line is a change directory command followed by a relative path, not absolute. In such cases, it is important where you run the script. (An absolute path would start with the filesystem root, i. e. /.)
If you run this script from a directory (I wouldn't call it a folder in this context) where the relative path opt-out-exam/abduvosid_malikov/IT does not exist, it won't cd into it. But it will make a new directory without any problem, it will also create the file and write a line into it.
So only the first line will fail if it's run somewhere else.
UPD: As Gordon Davisson pointed out, this means that you want to check whether the directory change actually took place or not.
Related
I am using an ssh account that connects to an external server, i have downloaded through guix some software like samtools and bedtools but when i try to use them in my directory it gives me this error:
-bash: samtools: command not found
In my direcory, however, there is the directry guix.profile and if I go into the bin folder of this, I have everything I downloaded.
What am I doing wrong?
Thank you
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To run a file from the shell you need two things:
The shell must find the file
Being in the same directory does not enable the shell to find the file. You have to either supply an absolute or relative path the file, or have the directory in your PATH environment variable
In simplest terms this means instead of
$ samtools
try
$ ./samtools
The relative path tells the shell it wants that file
To run it from another directory, either use the whole absolute path, e.g. /home/yourname/samtools , or move the file into a directory that is on your $PATH
The file needs to be executable
If the file is not executable you will need
$ chmod +x ./samtools
Lets say I have a folder called xfile, inside of it we have runthis which is executable.
So, in order to execute that, I have to cd xfile and then ./runthis. and it will work just fine.
But, If I have a script call it run.sh and do this ./xfile/runthis, it will says run.sh: line xx: ./xfile/runthis: No such file or directory
So, how to make it happend without doing cd? It's been bugging me alot lately.
The leading dot in your command ./runthis means "relative to the current directory". But when you want to call it from outside the directory, remove the dot and provide the absolute path of your executable file xfile/runthis. The same is true when you want to call it from your run.sh
I have a bash script that runs my Go program. That's all it does, and when I run it from the command line, it works fine.
But when I run it by double clicking on it in Finder, it returns
/Users/colin/go/metgen/metaphorgenerator.sh: line 2: ./binary: No such file or directory
So I made it echo it's working directory, and it just prints /Users/colin, my home directory.
How do I get it to run the code from the directory the file is in? (I want it to work no matter what directory it's in)
You need to point it to the location of the executable, either with a relative path from the working directory as in go/metgen/binary, absolute path like /Users/colin/go/metgen/binary, or absolute path based on the parent executable (unfortunately not reliable).
$0 is the full program name. So you can get the directory with HERE=$(dirname "$0").
Then, line 2 should have ${HERE}/binary.
Per the title, I'd like to have a .sh file which I can drop into a directory and then:
Run http-server (the simple node server) in the current directory
Open Chrome and point it to that server
The idea is that when I'm developing I can quickly run this bash file and see the current version of whatever html/css/javascript website I am working on. My issue is that if you run a command in a bash file, it isn't run in the current working directory, but rather in the root directory (as far as I can tell). So if I just write http-server in my file, it will run a server not in the current directory, but in ./.
To fix this, I want to cd to the directory first, and then run the script. current_dir=$(pwd) will give me something close to the current directory, but I can't put that directly into a cd command because it (1) doesn't have quotes around it, so spaces in directory names will make it not work, and (2) it starts with /C/ instead of /C:/. Can anyone advise me on how to fix this?
My current code looks as follows.
curr_dir=$(pwd)
cd $curr_dir
http-server
start chrome localhost/XXX
And, as mentioned, results in the http-server command being run in the wrong place:
Starting up http-server, serving ./
Available on:
http://192.168.56.1:8081
http://192.168.1.21:8081
http://127.0.0.1:8081
Hit CTRL-C to stop the server
e: For anyone who happens on this later, this isn't actually a problem -- see the accepted answer. I had another typo.
No; the commands you run always run in the current directory. Otherwise, if your hypothesis were correct, e.g. ls would always show the files in the root directory.
If you want to run a command which is in a different directory, you want
../relative/path/to/command
or
/absolute/path/to/command
Neither of these change the current directory of the shell. The current working directory of the process you create will remain the directory you were in when you run this command. (Even if you run it in the background and subsequently change to a different directory in your interactive shell, for example.)
If you want the command to run in the directory where the script lives on the disk, something like this can occasionally be useful.
cd "$(dirname "$0")"
but again, most of the time, you want and need your commands to run in the current directory.
(There are situations where you want a script to process data files in a fixed location, but these are rare exceptions. Until you have such a situation, consider it a bug to use cd in a shell script.)
If you have a command http-server somewhere on your PATH, just http-server will run that. You should normally not have the current directory on the PATH, but to run the binary in the current directory instead of from anywhere on the PATH, you say so:
./http-server
I am very new to bash and using .sh files. I am trying to run the program aescrypt by calling it in a .sh file as follows (aescrypt is in the same directory as the .sh file) :
./aescrypt -e -p password file.txt
It throws the following error:
./aescrypt no such file or directory
Am I doing it wrong?
ps- I realy don't want to add it to the PATH variable as I will be using this on more than one computer that resets every day.
The location of the script is irrelevant. The thing that matters is the working directory of the process executing the script. The simplest solution really is to add aescrypt to a standard location like /bin or /usr/bin. If neither of those is acceptable, perhaps /usr/local/bin is an option. Otherwise, just use the full path of aescrypt in your script. Either hard code it, or if it is in the same directory as the script, try:
$(dirname $0)/aescrypt ...
(Note that hardcoding is more reliable, but less flexible. If you move the executable, the script will break. But using dirname will break if the script changes directory during execution.)
how about if you call the program like ./aescrypt.sh, thats the way to call an .sh programm througt the terminal
First off all, you have also to change the permissions of the file to make it executable, the way to make that is to write in the terminal, the command:
sudo chmod 765 aescrypt.sh
For that you have to be located where the file is