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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2
votes
1answer
48 views

Execute commands from history that match regex or grep

I was wondering if its possible to execute commands from history that match a certain regex? I know you can do something like fc 232 248 And it will go into your history and then do revisions ...
0
votes
1answer
66 views

AWK is throwing an error “unexpected newline or end of string”

My Bash script: declare -a lang=('english' 'spainsh') sms="Free msg: Due to upgrades on apps you’ll need a new version by yyyy/mm/dd to app running. Visit a store or go to" url="google.com/UA2392 ...
0
votes
2answers
60 views

How to extract unknown arguments within a shell script?

I have a shell script that accepts a variety of options, some with arguments, some without, some short, some long. It should handle some of these options itself and pass on the rest it does not know ...
1
vote
1answer
48 views

How can I prepending a character for every output of a command?

I'm running commands which I want to specifically group them by every command, as shown in the example below. Tried printing with echo -e '| $line' but it only affects commands that output the text ...
3
votes
1answer
153 views

prevent a command from sending both stdout & stderr to any terminal or file [duplicate]

I would like to prevent my program from sending stdout and stderr to any terminals, files or devices. For this, I have three command crossing my mind, but I cannot distinguish their differences. Could ...
0
votes
0answers
38 views

How do I write a script for testing username/password? [duplicate]

I have about 500+ hosts I need to test a username/password combo to make sure there aren't any false positives in the list. I just need to make sure I can login and log out, no need to run anything ...
8
votes
1answer
233 views

Bash wildcard to match exactly n characters

Is there a wildcard in bash to match exactly 5 characters, shortening a pattern like ?????
0
votes
1answer
30 views

Dialog radiolist using dynamicaly defined array of choices

Following my previous question, I have write the following MWE to create a simple file selector by date filesArr=( $(ls -1rt ??????????_?) ) nfiles=${#filesArr[@]} iLastFile=$[nfiles-1] choiceArr=( ) ...
1
vote
2answers
63 views

Bash / Linux Tools for correcting xml

I am generating a set of 'xml' files from a 'csv' file. Some of the fields in csv file contain '&' and other invalid xml characters that need to be replaced with their appropriate xml counterpart ...
4
votes
1answer
174 views

bashrc lazy substitution

How does one get ~/.bashrc aliases to evaluate $() substitutions at run time, instead of at the time that ~/.bashrc is executed (when opening a terminal)? I run this command often enough that I would ...
2
votes
2answers
166 views

Extract group name from `id` and store it in a variable

$ id usera uid=830(usera) gid=799(groupa) groups=799(groupa) I need to extract the group name from the output of id and store it in a variable. In this case it's groupname=groupa
0
votes
0answers
27 views

mdoc warning: Empty input line #xx

while searching man pages using grep ( man tar | grep compress) I am getting this error: mdoc warning: Empty input line #xxx xxx can any number Is grep giving this error or something else? how can ...
3
votes
1answer
39 views

using shortcuts to move in bash command line [duplicate]

When I use Ctrl+Left_arrow or Ctrl+Right_arrow in bash, I move backward a "word" and forward a "word" respectively. I belive, this is defined in /etc/inputrc # mappings for Ctrl-left-arrow and ...
1
vote
0answers
23 views

How to get stdout of process? [duplicate]

I started a process from the command line, but the window server died. However I see the process I started is still running. Is it possible to connect a terminal to the process to see its output? ...
5
votes
3answers
290 views

How can I make a script take multiple arguments?

This is a very simple script #!/usr/local/bin/bash set -e if [ "$#" -lt 1 ] then echo "Please insert at least one argument" exit else echo -e "\c" fi if [ -h "$1" ] then echo "$1 is a ...
3
votes
2answers
314 views

How to print out only the script name?

[username@notebook ~]$ cat foo.sh #!/bin/bash echo "$0" [username@notebook ~]$ ./foo.sh ./foo.sh [username@notebook ~]$ Question: How can I output the "foo.sh"? No matter how was it executed.
4
votes
2answers
337 views

What defines “ll” in Fedora?

In Fedora, instead of typing ls -l, you can type ll. What causes this behavior? I've installed a new Debian system that does not appear to have this functionality. They're both running Bash. I can ...
0
votes
2answers
31 views

Add some text while output to file

Assume I have this command: ./clang-$j.out >> clang-result.txt and the each output for clang-$j.out is a fixed-length hash value (each program per line), however, I want to distinguish them by ...
1
vote
1answer
75 views

How to run a shell script (bash) on a chromebook?

I have a shell script and I need to run it in order to connect to a remote ubuntu linux machine having encrypted HDD, in order to enter the passphrase. There's a shell script for this, but I have a ...
9
votes
2answers
414 views

Jump out of a process when it get stuck

I have written a loop to iterate all .out c binary file and copy their outputs into a text file (the output for every binary file is just a one line hash value, one line output for one program). Here ...
1
vote
3answers
67 views

update-rc.d doesn't accept the header of a script file

I have beagleBoard and I want to start my script at boot time ( boot/reboot). So, i ran command: update-rc.d GatewayStart.sh defaults Output which says: header is rejected ...
3
votes
2answers
116 views

Where does the TERM environment variable default get set?

When I open a terminal window with the GNOME Terminal emulator in the desktop GUI the shell TERM environment variable defaults to the value xterm. If I use CTL+ALT+F1 to switch to a console TTY ...
0
votes
2answers
22 views

How to print arguments from a known element until an unknown element of an array with Bash

I am having a blonde moment. This is my data from myfile.csv 1429829254,e,SE,StckXchg,HDCU3000623,d,scan,253,47968,94,1420824420,JSSE-213,199,BS,KIT,*OUT* ...
4
votes
3answers
252 views

Is there a way of reading the last element of an array with bash?

If I have an array with 5 elements, for example: [a][b][c][d][e] Using echo ${myarray[4]} I can see what it holds. But what if I didn't know the number of elements in a given array? Is there a way ...
0
votes
0answers
41 views

tmux status bar path customization with sed

On the server I connnect to my home path is like this:/home/junk1/junk2/user. I can use the sed command pwd | sed -e 's|^/\([[:alnum:]]*\)/[[:alpha:]]*/[[:alpha:]]*|/\1|' to shorten the directory path ...
1
vote
2answers
61 views

Change color of input text, not output [duplicate]

I need to capture screenshots of the terminal where the typed commands visually "stand out" from the rest. Right now I'm using this to make my typed commands "red": PS1='\[\e[0;31m\]\u\[\e[m\] ...
3
votes
2answers
284 views

Why I should avoid loops in shells? [duplicate]

The following link recommends against using loops in shells. bash variables in for loop range Why is this? Here is an example loop I just happened to be looking at when I came across that answer: ...
1
vote
0answers
16 views

Is there a way to make bash recognize aliases with prefixes [duplicate]

Assume you defined the alias alias grep='grep --color=auto' in ~/.bashrc. Then invoking sudo grep wouldn't trigger the alias to be used. Is there a way to do so? If yes, would that solution be ...
1
vote
2answers
67 views

shell script to get collect pixel size of image

I'm trying to create shell script that returns the largest picture in total dimensions pixel size? For example: I have many directory over 7000+, each directory have images: dir_1/ picture_1.png = ...
3
votes
2answers
230 views

Why do I receive a “/bin/bash cannot find command” error for an alias?

I am using multiple python, I alias python3 to py: alias py="/opt/python3.4/bin/python3" I want to run python in vim so I write this: map <F9> :call SpecialCompileRun()<CR> func! ...
0
votes
1answer
38 views

Multiple input files and output files in awk

I have a folder full of text files named 000.txt to 181.txt. How can I process all of them with the same awk script (program.awk) and send them to their respective output files (output000.txt - ...
0
votes
1answer
32 views

Persistent Bash history between detached processes

I haven't yet been able to find this among the Bash documentation so I was hoping it could get answered if I asked it here. Is there any way that I can, on execution of a script, branch its history ...
5
votes
3answers
257 views

Is it possible to echo into a file, but use indenting in the shell script source? [duplicate]

If I have some nested and indented statements that echo a multi-line string into a file, the indents from the original shell (in my case bash) will be carried over into the target file. To avoid ...
1
vote
1answer
49 views

Extracting duplicity backup data

I've made some backups of my previous systems using Deja Dup (duplicity). In my current distribution it's not available, so I've simply extracted the data. Now in order to make that data meaningful ...
3
votes
2answers
44 views

Remove data from the STDIN stream buffer of another TTY session

I encountered a problem the other day while running multiple tty sessions in separate terminal windows. I was running a expensive disk access command and was waiting for it to return. Meanwhile I was ...
1
vote
3answers
57 views

Last exit status from within script without source

Supposing someone invokes a non-existent command, the only way I know to retrieve its error status from a script I execute right after is by using source I.e., let's say this script's name is dummy ...
1
vote
1answer
60 views

Shell intervals using awk

I have a file a 10:10 10:30 b 12:15 13:15 c 16:54 17:54 and I need to enter interval for example 10:15 so my output should be a 10:10 10:30 How I need to do that using awk?
0
votes
1answer
50 views

Run script from GUI with terminal output

I would like to run a script from the GUI. For example a simple echo "hello" from the right click context menu. In my case I would set up an action in thunar like this: Then it appears in the ...
1
vote
2answers
51 views

Using sed to replace javascript code in multiple files

I need to replace an old google analytics code with the new universal tracking code in lots of static html files. The old code looks like this: _uacct = "UA-XXXXXX-X"; urchinTracker(); The new code ...
1
vote
1answer
43 views

Get first/second file column

I have two for loops here for i in $(cat "firstFile.txt") do for j in $(cat "secondFile.txt") do if [ "$i" = "$j" ]; then echo $i[$2] # use first file second column ...
4
votes
1answer
113 views

Redirection to file does not work properly

I have here a bash script: #!/bin/bash TARGET_FILE=ping_result.txt # declare the target ip addresses declare -a ips=("XXX.XXX.XXX.XXX" "YYY.YYY.YYY.YYY") function print_and_log() { echo "$1" ...
4
votes
1answer
53 views

Using nice on bash (or other) subshell?

Say I'm working on a sluggish system and notice (say via top) that CPU usage is up around 100%, but I don't want to kill the process. If I want to do other work on the machine and just make that ...
0
votes
0answers
33 views

output in columns [duplicate]

i am trying to put my data after a snmp walk in a table this is my code: for i in `cat $Rep_Scripts/IP_ALU_LIST.txt | awk '{print}'` do read hostname ip <<< $(echo $i |sed 's/;/ /') ...
5
votes
3answers
335 views

Compare the heads of two files in bash

I can do diff filea fileb to see the difference between files. I can also do head -1 filea to see the first line of filea or fileb. How can I combine these commands to show the difference between the ...
2
votes
1answer
36 views

Expand variable in brace expansion [duplicate]

I am trying to enumerate a range of integers using a variable but having some trouble. When I type echo {1..5} I get 1 2 3 4 5 However, when I type a variable, I am unable to get the ...
2
votes
1answer
31 views

How to download a lot of documents on the terminal from a server?

I have to write a bash script (.sh) with less than 300 characters which downloads all of the genomes 22 in this server ftp://ftp.ncbi.nih.gov/genomes/Homo_sapiens/ (the ones with fa.gz extention) and ...
1
vote
3answers
65 views

bash: Saving aliases beyond one session

Recently, I've been fiddling around with Linux's terminal commands to try and get a better feel for the system. I was happy to know that I could give commands a different name in order to call them, ...
0
votes
1answer
25 views

need help with inserting variables in a file path on GNU linux (SLES 11)

I am tryin to insert 3 variables to build a path, but unable to get it . I am trying the below log_path="/vol02/logs/$dname/logs/103602_$msname/${msname}_start.log" dname=cfp msname=cfp003 i get ...
1
vote
1answer
40 views

How to wrap bash commands after adding color

My current .bash_profile is equal to the below. I add some color and add a command that outputs whether or not I am in a git repository to my PS1 for my bash profile. ORIG=$PS1 ...
1
vote
1answer
34 views

How use '(' token when using it for searching with ag / awk?

$ ag findVersions( src/java/com/google -bash: syntax error near unexpected token `(' I tried quoting it, escaping it, both were not suitable. $ ag findVersions\( src/java/com/google ERR: ...