Questions about bash only, as opposed to other Bourne/POSIX shells. For all Bourne/POSIX-style shells, use the /shell tag instead.

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0
votes
2answers
35 views

Auto Delete Inactive files after x

Is there a way I could delete certain folders after x amount of days of inactivity? I was thinking of using cron but that wouldn't take the inactivity part into consideration. Is there any Debian ...
0
votes
0answers
30 views

The program called by the init.d works by itself, but not when the init.d itself runs

I currently have two programs, my_sql_auto_update.sh and my_sql_auto_update_initd.sh, the latter is the init.d script located at ~/etc/init.d/ which [should] run the my_sql_auto_update.sh. The ...
4
votes
2answers
73 views

Expand wild cards in command before executing it

Suppose I want to type something like this: rm build/* tmp/* I am about to run it but I want to expand the wildcards before executing so I can verify what is about to happen. How can I do this? ...
0
votes
2answers
67 views

bash execute command for X arguments at a time

I have a list of files stored in txt file. ./test7 ./test4 ./test1 ./test5 ./test6 ./test10 ./test8 ./test2 ./test9 ./test3 I want to run a command on all those files but I want to sleep 1 second ...
5
votes
1answer
452 views

Write default array to variable in Bash

I was expecting excludes="${excludes:-( ${default_excludes[@]} )}" to be an array if $excludes is empty. Unfortunately the stuff after :- is taken to be a string. Did I miss some syntax contortion, ...
8
votes
3answers
21k views

remove particular characters from a variable using bash

I want to parse a variable (in my case it's development kit version) to make it dot(.) free. If version='2.3.3', desired output is 233. I tried as below, but it requires . to be replaced with another ...
3
votes
4answers
3k views

Wait for multiple files to be finished downloading

I have the following script which checks if there is a file in a folder and if the file is stable (this is for large video file I am receiving). #!/bin/bash cdate1=$(date +%Y%m%d-%T) ...
1
vote
2answers
79 views

check if a variable is in list

to check if a word is in a list of words or no I wrote this script: tr -s '[[:blank:]]' '\n' < t.txt | while IFS= read -r word; do if [[ "$word" =~ $(echo ^\($(paste -sd'|' ./champs.txt)\)$) ...
1
vote
2answers
41 views

I cannot understand bash script results

Here is the script: echo '1 2 3 4 5 6' | while read a b c ;do echo result: $c $b $a; done The result is 3 4 5 6 2 1 Can someone explain why?
1
vote
1answer
28 views

How to display a Image on a remote linux machine through ssh

I have two computers, one running windows(WIN7) and the other running linux(SUSe). I'm wondering if there is a way to ssh(Putty) into the linux machine and run a command to have a image display on the ...
0
votes
1answer
33 views

Error not found [closed]

I wrote this script to encode / encrypt data from a sql query by changing the names of tables and fields (I played on the ASCII character codes). #! /bin/bash chr() { [ "$1" -lt 256 ] || return 1 ...
-2
votes
1answer
95 views

Sqlplus: Command not found

I have two virtual machines ubuntu, one is a server when I installed oracle 11g express, and the other is a simple client. My goal is to run an sql query remotely from the client machine. So I ...
1
vote
1answer
91 views

Sed command that would ignore any commented match

I'm trying to create a sed command using regex in order to substitute something in a text file only if it is not commented but I'm running into some troubles due to my almost non-existent knowledge of ...
21
votes
12answers
8k views

Object-oriented shell for *nix

Preface: I love bash and have no intention of starting any sort of argument or holy-war, and hopefully this is not an extremely naive question. This question is somewhat related to this post on ...
0
votes
0answers
16 views

How to find last x minute internet usage

How can i find out the last X minute download bandwidth in megabyte? i want to use it within a bash script.
1
vote
3answers
98 views

Bash long string, no word splitting?

I want to tidy up some script with long commands, so that for example: { somecheck || somecomand "reallyreallyreallyreallyreallyreallylongstring" } &> /dev/null & becomes something like: ...
2
votes
1answer
33 views

How can I popd to a specific directory?

I have used pushd to move about to various directories and now If I run dirs -v I get: 0 ~/Desktop 1 /etc 2 /var/log 3 ~/Downloads 4 /tmp How can I popd to a specific directory in the ...
9
votes
3answers
1k views

Why does “$(( ~33 ))” produce -34?

$ echo $(( 255 )) 255 $ echo $(( 33 )) 33 $ echo $(( ~33 )) -34 $ echo $(( ~255 )) -256 $ and my kernel is: $ uname -a Linux HOSTNAME 3.2.0-40-generic-pae #64-Ubuntu SMP Mon Mar 25 21:44:41 UTC ...
1
vote
2answers
56 views

How do I make a BASH loop

I'm very new to bash and Linux and I was wondering how I could make a bash loop so that when it runs, it will ask you how many times to run, and it will run that many times. I did it in LUA but I ...
2
votes
2answers
63 views

Why am I getting “invalid max count” from grep in an alias?

So the idea is to create an alias that will search my alias's for me. I have quite a few. dude@gnarleybox:~$ grep alg .bash_aliases.sh alias alg='alias | grep ' dude@gnarleybox:~$ alias | grep alg ...
0
votes
1answer
31 views

How can I get this array of numbers sorted? [closed]

I have an array called colNums that looks like this: 1 5 4 2 2 7 When I print the array with echo "$colNums" it prints like that. I want this list sorted. ...
2
votes
3answers
78 views

bash: error handling on find -exec

I was using this little script to find malformed images: find -name '*.jpg' -exec identify -format "%f\n" {} \; 2>errors.txt It worked well enough, but now I need to modify it slightly. Instead ...
1
vote
0answers
23 views

What Does the Output of “--help” Mean? [duplicate]

When using the --help option of a terminal program, a lot of output is produced. It usually starts with Usage: and then a bunch of things and brackets and parentheses. My question is, what doe the ...
1
vote
1answer
56 views

Running some parts of a script as an unprivileged user with shell environment

I am creating an instance configuration script that sets up a machine. I am running the script via sudo i.e. sudo run.sh. Most of the steps require root access but some of the script's steps do no ...
2
votes
1answer
48 views

Bash - Command substitution adds single quotes

I have a problem with bash behavior while evaluating grave accents. I want to run find with optional -name: find -name "*.log" works fine, but when i want to get the -name part from nested script ...
0
votes
0answers
43 views

Counting program fails in arithmetic test

having a little trouble with this rather basic script. This script works on Bash in my macbook pro, but not on my Linux Mint desktop, which also uses bash. I can't figure out what's wrong with it, ...
0
votes
1answer
47 views

Print file name,Modified Date and Size with Header

How do I print file size, file name and modified date with header.Till now I have come up with: find . -regex '.*\.csv' -execdir stat --printf '%n,%y,%s' {} \; How to add header and do not print ...
1
vote
2answers
59 views

Using command substitution

The shell variable number contains 1 1 1 1 1 separated by tabs. I want it to contain only the first 1. I'm trying number= $(echo "$number"| cut -f 3 ) and I get the error "1: ...
0
votes
2answers
39 views

How do I run find, maxdepth and other commands on lcd while using ftp?

I have got the command working locally using normal commands. I now need it to run while using ftp. I understand I need to use '!' And instead of copy I will need to use put so it works on the lcd, ...
4
votes
4answers
413 views

How to capture command line input into logfile and execute it at the same time?

Let's say I issue some commands on the command line: #capture what follows $ echo "foo" foo # don't capture $ echo "bing" bing # capture again $ echo "bar" bar How can I log commands selectively ...
9
votes
2answers
259 views

How to access the second argument from the last command in the history ?

I am starting to learn some Regex, therefore I use this command repeatedly: grep pattern /usr/share/dict/american-english Only the part with pattern changes, so I have to write the long expression ...
0
votes
1answer
32 views

Copy tree directory from specific point

I am now sure how to word this, but: I am copying all the newest .zip files each recursive sub directory inside this original folder: "/Users/Stu/Documents/Hoffi Work/FTP Backup Shell ...
4
votes
2answers
100 views

Safely exiting while loops in bash

Say I have a bash script that does: while : do foo done I would like to be able to run this script from the console and be able to exit it at an arbitrary time as long as it happens in between ...
4
votes
2answers
964 views

Sudo Su automated login

I want to automate the login process with sudo su. I have seen lot of questions on these, but none of them are working for me. Automate login with sudo and su Here's my what I tried so far echo ...
5
votes
6answers
4k views

Calling multiple bash scripts and running them in parallel, not in sequence

Suppose that I have three (or more) bash scripts: script1.sh, script2.sh, and script3.sh. I would like to call all three of these scripts and run them in parallel. One way to do this is to just ...
2
votes
3answers
175 views

AWK & Bash: Checking that a User's Home is Owned by the User

I'm trying to cycle through /etc/passwd with a single-line command in order to find those users who have a home directory which is not owned by the user, but I'm VERY new to bash programming, and I ...
0
votes
0answers
11 views

What shell extension recommends packages if command is not found and how to update it? [duplicate]

I know this question might sound a little strange but i really don't know how to describe it better. On my Debian system I have a shell extension for bash that, whenever I enter an unknown command, ...
1
vote
1answer
451 views

how to locally redefine 'command_not_found_handle'?

I'd like to make a particular bash script failfast when it cannot find a command, while retaining globally the usual friendly command_not_found behavior. E.g., if I save the following to /tmp/foo.sh, ...
7
votes
3answers
3k views

Why a long delay after command not found?

Often when I mistype a command such as ls (e.g. I hit ENTER before I type 's') there is a long (~2s) delay after the terminal displays: bash: l: command not found... I can understand the reasons ...
1
vote
1answer
65 views

Running every command through another

I'm setting up a system in which any external command that does something with real effect must be crypthographically signed before before the system will execute them. The restrictions are in place ...
2
votes
3answers
161 views

KSH/BASH Maximum size of an Array

What is the maximum size of array for ksh and bash scripting ? Example: Suppose I have an array of 10 elements than what will be maximum number of string count that a particular index of an array can ...
2
votes
2answers
521 views

Script that unpacks a initrd, allows editing of the preseed.cfg and the packs it to cpio and gzip again

I want to program a script that allows what is said in the title. So basically I gunzip the initrd, than unpack the cpio, open vi to allow editing, save, pack with cpio, and gzip again, so nothing ...
0
votes
5answers
119 views

Read File word by word

My problem is to read a text file word by word and recovers every word in a variable. I tried to do: while read ligne; do { for ( i=1; i<= length ($ligne); i++); do { var=$(awk '{print $i}' ...
0
votes
2answers
34 views

How to scrape multiple IP's and add in a script as a variable?

I am trying to add in my script an awk statement or a: if; else; then if eth0:4 is a match then put in eth0:4 IP How would you get the IP in your script as a variable if you have multiple IP's ...
3
votes
3answers
14k views

Pass command line arguments to bash script

I am new to bash script programming. I want to implement a bash script 'deploymLog', which accepts as input one string argument(name). [root@localhost Desktop]# ./deploymLog.sh name here I want to ...
0
votes
0answers
71 views

shell script prompting for password but not taking it while doing tar

In my shell script, I have following lines: function tarIt() { FILE_OWNER=$1 TAR_FILE_NAME=$2 FILE_NAME=$3 su - $FILE_OWNER -c "tar -czf $TAR_FILE_NAME $FILE_NAME 2>&1" if [ ${?} ...
0
votes
0answers
23 views

Is there a way to add a timestamp to the logs for qsub job?

I'm submitting jobs on a cluster via qsub but the error/output logs don't have a timestamp, making debugging more difficult. Is there a way to add timestamps to the logs in the bash script? Appreciate ...
2
votes
4answers
105 views

How to make diff command ignore certain lines of second file(bash)?

For example: file1.txt: I need to buy apples. I need to run the laundry. I need to wash the dog. I need to get the car detailed. file2.txt I need to buy apples. I need to run the laundry. I need ...
0
votes
3answers
49 views

copy the contents of a variable in a text file

I know this is a stupid question but I want to know how I can put the contents of a variable in a text file. This variable is a string that I want the code with the base64 command.But this command ...
0
votes
0answers
24 views

Linux, dev/tcp validation and kill the process with timeout

I have this part of code, I need to validate if the connection was ok or not, AND, if the process is running more than 3 seconds, it will be killed. But, I dont know how to keep the value of the ...