All Questions
17 questions
1vote
2answers
213views
Redirect to a filename that will be a variable and contain a command substitution
I'm using nmap to scan a network and then create an XML file that contains the scanned information. I want that XML file to contain the date of the scan so that each file is unique and I can see the ...
0votes
2answers
248views
How to get the Path difference and store it in a variable
Suppose I have two paths. Path1 which is static and path2 which is dynamic. Example: Path1= /tmp/folder/ Path2= /tmp/folder/dir1/dir1_2 Result: Diff= /dir/dir1_2 I want to achieve as above example....
7votes
3answers
868views
Remove repeating string pattern from variable with POSIX parameter expansion
I wanted to use 2.6.2 Parameter Expansion to remove leading characters from a string, but was surprised to find out that "Remove Largest Prefix Pattern" doesn't automatically repeat the ...
- 3,504
9votes
2answers
793views
In POSIX scripting, is x=$y always equivalent to x="$y"?
Are x=$y and x="$y" always equivalent? Didn't know how to search for this. So far, I've always been using x="$y" to be "on the safe side". But I used x=$1 at one point ...
- 3,504
4votes
2answers
6kviews
How to dynamically set a variable name in shell script?
I am looking for a sh equivalent of the following (yes, really.) #!/bin/bash exe1='filepath' n=1 var=exe${n} echo ${!var} Where the echo should output filepath. I want to use plain sh. I have ...
- 222
0votes
1answer
101views
problem with dynamic variable on a bash script
I would like to obtain a .txt file of the following format: chr1: 3 chr2: 3 chr3: 3 I use the following script but give different errors: #!/bin/bash touch number_samples.txt for i in {10..22} do ...
- 117
1vote
4answers
989views
Add Space Before Last Character in Variable
I have a variable that contains some numbers then a letter example: 242M I need to add a space right before the last character in that variable so that when echo'd it would look like 242 M I've ...
- 13
0votes
2answers
8kviews
Bash-Script: How to insert Variables into Bash-Script?
The following bash script is working completely fine: #!/bin/bash echo '!PaSsWoRd!' | openconnect --csd-wrapper=/home/user/.cisco/csd-wrapper.sh --authenticate --user=abcde123 --authgroup="tunnel My ...
- 1,046
3votes
1answer
5kviews
In bash, how can I export/set a global variable from a read funtion inside a script, for use in a second script and a config file later on?
For example. I have 2 discrete scripts, which I want to remain and run separately. Script 1 utilizes a read function asking for a desired filename lets just say name1, does it's thing, and outputs the ...
0votes
1answer
171views
How to make variables be accessible from scripts [closed]
In Ubuntu 16.04 I executed a script (script 1) which by itself executes two other scripts (script 2 and script 3). Script 3 contains a variable substitution (${x}) for a variable already declared in ...
1vote
1answer
536views
pass the value of variable from a script to another script from another server
I have a script that will ssh to another server. Script A will get the value of $variableA, then will ssh to another server to execute a script B which will need the value of $variableA. I tried ...
- 11
1vote
1answer
784views
For with read value
In what way does the final value of number being assigned by read var number (and we enter 5) and number=5 differ? I was making this for loop: read var number #number=5 factorial=1 i=1 for i in `seq ...
- 155
0votes
1answer
27kviews
Checking if string exists in file with cat | grep
Good day all Purpose: checking if a string exists in a file and running actions accordingly if [ -z 'sudo cat /etc/sudoers | grep "$USER ALL=(ALL) NOPASSWD:ALL"' ]; echo "no output, cont." || echo "...
- 306
2votes
1answer
596views
I want to use the variable declared inside an SSH session to be used locally in my shell script
Whenever I try to use the variable declared inside my SSH session it gives me blank output. Here is the code which I am trying to execute: ssh -T host <<\HERE export usage1=$(df -h |grep /nas/...
659votes
4answers
506kviews
Using "${a:-b}" for variable assignment in scripts
I have been looking at a few scripts other people wrote (specifically Red Hat), and a lot of their variables are assigned using the following notation VARIABLE1="${VARIABLE1:-some_val}" or some expand ...
- 7,519
