Questions about shell scripts, executable files that are interpreted by a shell (bash, zsh, etc.).

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1answer
34 views

how to use the eval command in order to print the value of parameter

Please advice how to use the eval command in order to print the parameter value for example bash a=1 b=2 c=3 for i in ` echo a b c ` > do > echo "$i=` eval $i ` " > done bash: a: ...
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4answers
42 views

Bash one liner to change configuration parameters

I have a config file with following structure. ValueOne = 1 ValueTwo = 2 ValueThree = 3 I want a one liner bash script to find ValueTwo and change the value to 22222. Any idea? Not School Thing
1
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4answers
77 views

Compare two numbers read from a file

I have a script that reads a file with a standard format where the 9th word is a number. I am trying to compare the number that is read from the file. I am able to read the line correctly and it works ...
5
votes
4answers
565 views

generate consistent machine unique ID

Can we generate a unique id for each PC, something like uuuidgen, but it will never change unless there are hardware changes? I was thinking about merging CPUID and MACADDR and hash them to generate ...
0
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1answer
67 views

Parse lines of output from bash loop

I'm trying to parse the output of commands run in a bash loop. Here is an example: $ for i in `git log --format='%H'`; do echo $i ; git branch --contains $i; done | head -n 8 ...
5
votes
1answer
604 views

Why do I have to escape a “dot” twice?

I know that we can escape a special character like *(){}$ with \ so as to be considered literals. For example \* or \$ But in case of . I have to do it twice, like \\. otherwise it is considered ...
4
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1answer
294 views

sudo: unable to execute ./script.sh: no such file or directory

I'm stumped. I have a script in my /home directory which is executable: [user@server ~]$ ll total 4 -rwx------ 1 user user 2608 Jul 15 18:23 qa.sh However, when I attempt to run it with sudo it ...
0
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1answer
24 views

How to dynamically chose PBS queue during job submission

I run a lot of small computing jobs in remote cluster where job submission is managed by PBS. Normally in a PBS (bash) script I specify the queue that I would like to submit the job through the ...
2
votes
0answers
98 views

Securing a script a little more

I currently have the following script which works fine: #!/bin/sh user="$(zenity --entry --title="Username" --text="Username")" pass="$(zenity --password --title="Password" --text="Password")" ...
0
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1answer
31 views

Reusing user input in a script

I have the following script which works: #!/bin/bash xfreerdp /cert-ignore /f /v:farm.company.com /d:company.com /g:rds.company.com /u:$(zenity --entry --title="Username" --text="Username") ...
0
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1answer
128 views

Bash script question - skip enter key press [duplicate]

Here is a portion of my script: read main_menu case "$main_menu" in "0" ) exit ;; "1" ) cp /etc/bamt/cgminer.conf.X11 /etc/bamt/cgminer.conf; sudo mine restart; ...
1
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1answer
37 views

Bundling of dependencies with shell scripts

Shell scripts often have to depend on tools that may not be installed on the users' computer. To circumvent this problem, many scripts have multiple fallbacks. IMO doing such things only leads to ...
3
votes
1answer
67 views

Convert json numbers to strings in the shell

When parsing json, the command-line tool jshon converts numbers to scientific notation, and sometimes tries to round them. To avoid these problems, I want jshon to consider these numbers as strings. ...
2
votes
1answer
82 views

Bash Script Permission denied & Bad Interpreter

I'm on a kali linux 64 bit. I have created a python script which takes 2 arguments to start. I don't want to type out every time the exact same paths or search in the history of the commands I used ...
2
votes
2answers
114 views

How to force watch to run under bash

The problem is that when watch is executed it runs sh and I get this error: sh: 1: func1: not found here is the code: #!/bin/bash func1(){ echo $1 } export -f func1 watch func1
5
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3answers
216 views

How to extract URIs from files

How can I extract from a certain number of files all the URIs like magnet: file:? I'd like to have one URI per line as the output. I'd like to use bash to achieve this, but any suggestion is welcome. ...
4
votes
5answers
299 views

Delete the last character of a string using string manipulation in shell script

I would like to delete the last character of a string, I tried this little script : #! /bin/sh t="lkj" t=${t:-2} echo $t but it prints "lkj", what I am doing wrong? Thank you in advance!
3
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3answers
144 views

Pipe in a shell script

I have done this little script : #! /bin/sh path="foo" while touch $path ; do path=./${path} done echo "echec avec le nom $path qui fait" echo $path|wc -c echo "caracteres" How can I ...
2
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1answer
66 views

SSH config file + shell script help

Well, what I want to do seems a bit convoluted but its the only way I can think of to get the result I want. So here goes. I want to automate ssh to my Pi, in the following fashion: My Pi boots up ...
1
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0answers
7 views

Automating minisat solutions

I'm a unix noob and need a simple (bash) script. I am solving SAT instances using minisat. The syntax is minisat inputfile outputfile. However, it only returns one solution. To find all solutions I ...
4
votes
1answer
74 views

Communicating from bash with grunt shell

I'm tired of the slow startup time of hadoop fs just to query HDFS. This isn't a problem with HDFS itself though, because using HDFS file system commands within the Pig "grunt shell" is pretty fast. ...
0
votes
2answers
105 views

If UID=1000 continues, else exit

I am wondering how to implement the following in a bash script. if UID=1000, continue else exit confirm choice (y/n)
0
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1answer
39 views

elif [ “$input” = “no” ]; then go the next statement

#!/bin/bash input="" echo "Does a wall needs to be sent?" read input if [ "$input" = "yes" ]; then echo "Sending message to all user about a system reboot or shutdown"|wall elif [ "$input" = ...
0
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1answer
49 views

Syntax error in bash script: near unexpected token `else' [closed]

#!/bin/bash input="" echo "Does a wall needs to be sent?" read input if [ $input="yes" ]; then echo "Sending message to all users" echo "" else if [ $input="no"]; then exit fi fi echo ...
3
votes
2answers
47 views

Filtering images according to file name, why?

When filtering the images using the below code, I also need to filter files. For example,IMG_0079.JPG.JPG, when running the code below it's allowing files with additional .JPG to get filtered out, ...
3
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3answers
61 views

Moving latest files from one directory to another

I'm trying to move newest files from one directory to another directory. The find command finds the files but not moving them to another directory. The destination directory exists. $ cd ...
2
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1answer
95 views

Why does this script work on Ubuntu, and not Debian?

I run a simple minecraft server. I made a script awhile ago for Ubuntu that would automatically create a Gnu screen and start said server. I decided get a new server with debian instead. Now for some ...
3
votes
2answers
34 views

Comparing an string by value of a floating number to a number

I wrote the code below: for j in `cat output_10.txt` do dri=`echo $j |cut -d':' -f1` nu=`echo $j |cut -d':' -f2` tot=`echo $j |cut -d':' -f3` fre=`echo $j |cut -d':' -f4` if [ $fre > 2 ] ...
1
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1answer
27 views

How to slice a text file into several files of 100 lines each? [duplicate]

My question might be quite unclear here. I have a giant text file with values that looks like this 0.00601233 0.000139403 0.000133679 0.000139497 0.000141683 0.000141888 0.000138646 0.000133465 ...
3
votes
1answer
45 views

Why does the read command not take interactive options when run by sh?

I want to download a provisioning script that reads some configuration parameters via read, and execute it: curl http://example.com/provisioning.sh | sh The problem is, that the read command in the ...
3
votes
2answers
152 views

using “ifne” in Bash pipe

In my script, I am using the ifne utility from the moreutils package. The line can be simplified to the following: printf "asdf\n" | ifne cat - && echo "stream not empty" ifne only ...
3
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2answers
111 views

Can we find page count of a file in Unix/Linux?

I want to count number of pages in the file /var/log/messages, so that I can use pr command to start printing from the page I want to. For example, suppose that /var/log/messages file contains 300 ...
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0answers
14 views

FFMPEG stream won't show up on Justin.tv

INRES="1366x768" # input resolution OUTRES="1366x768" # Output resolution FPS="35" ...
2
votes
1answer
41 views

Controlling bash script concurrency, flock inheritance

I have a bash deployment script that handles deploying updated code to a Tomcat instance on CentOS, however, both Chef and RunDeck may invoke the script, and since Chef runs periodically there is a ...
2
votes
2answers
36 views

Merging files by rows

Is it possible to copy the whole rows of File1 in a new File3 following the instruction given by File2 by using a simple bash script using sed or awk? File1: /*two or more columns*/ AC 456324 DC ...
2
votes
1answer
97 views

merge csv files by first column

I have 3 csv files like this. csv 1: 1,aaaa,bbb,2014-04-01 2,qwe,rty,2014-04-03 3,zxc,cvb,2014-04-05 csv 2: 2,j,k,2014-04-01 3,a,s,2014-04-04 5,g,h,2014-04-08 csv 3: 2,a,s,d,f,g,2014-04-01 ...
2
votes
1answer
56 views

setenv not working in tcsh

I am trying to install a program on my brand-new CentOs. The installation requires setenv, which apparently does not work, not even in the tcsh shell. Can anyone give me some advice? [Anna@anna ...
1
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1answer
70 views

bash: syntax error near unexpected token `('

I am trying to concatenate some files side by side. I use the pr command in the terminal. It works well, but when I use it in a shell script, I get the following error message: syntax error near ...
1
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0answers
51 views

Sourcing nested sourced bash script multiple times causes an infinite loop [closed]

I have a cronjob that sources a configuration file, so as to put some variables in the environment, and then runs a script. This config script sources another more general config file that sources ...
3
votes
1answer
17 views

How to execute as the logged-in user in a sudo script (OSX)?

Is there a way to switch contexts like that? The script in my specific case is an installer postinstall script, which requires sudo privileges only for some of the tasks and requires the logged-in ...
0
votes
1answer
46 views

Converting windows date logic into Unix [closed]

I had coded the below logic in Windows batch scripting and I need to replicate the same in Unix. # Calculating Yesterday's Date for /F "tokens=1-4 delims=/- " %%a in ('date/T') do set DY=%%c for ...
1
vote
2answers
72 views

SCP Automation in production environment [duplicate]

I want to implement the use of scp command in a production environment. I don't want to provide my password in the automation script. Is there any way? I need step by step solution.
1
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3answers
54 views

what does the -z flag mean here

What does the -z flag mean in the code below: if [ -z $TEST_PARAM ]; then And is there a list of such flags? For a flag like ls -l, I know where to find it, but for a single flag, I didn't get any ...
4
votes
4answers
278 views

what does $* mean in shell [duplicate]

What does $* mean in shell? I have code two function, run_command and run_test, they are called like this: if [ -n "`echo ${GOAT_COMMANDS} | grep $1`" ]; then run_command $* else run_test $* fi ...
2
votes
1answer
36 views

Using xargs with git

I am trying to practice using xargs. I tried the following, passing the SHA1 via xargs: $ git show SHA1 --name-only I also tried: $ git log --author=jim --grep="patch" |head -n 1|cut -d ' ' ...
5
votes
1answer
162 views

ifconfig -a in a shell script

I am writing a shell script to start my network in my virtual machine on boot, since it does not do this right away for some reason with a snapshot of a virtual machine. Since the eth device starts ...
5
votes
2answers
120 views

Is there a way to make this one-liner faster?

Context I have a directory of thousands of zip files that are dated in the form YYYYMMDD_hhmmss.zip and each about 300K. Within each zip file is about 400 xml files each about 3K. The problem I ...
2
votes
2answers
178 views

Store all dates in a given date range into a variable

I want to store all possible dates between two user input dates. The input will be as like 20140605 and 20140830. I want to store every date between the given dates into a variable using a loop so ...
1
vote
4answers
85 views

Extracting a string from fdisk command

I want to write a shell script, which will run fdisk -l and extract a string /dev/sdbn from the output of fdisk -l. Using extracted word I want to mount it to /mnt. For Example: Disk identifier: ...
1
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1answer
65 views

Bash Script Display Remote Screen Session to User

I'm kind of new to bash scripting and I'm having trouble figuring out how to accomplish this. I'm working on a script that is designed to backup and manage a java application that runs within a ...