The shell is unix's command-line interface. You can type commands in a shell interactively, or write scripts to automate tasks.
1
vote
2answers
33 views
cat files in current folder and all subfolders
I want to cat a file in current folder and all files in all subfolders (and subsubfolders).
Here is my directory structure
$ tree
.
├── f
│ └── foo
└── yo
I want to cat foo and yo.
I've tried ...
38
votes
8answers
25k views
Colorizing your terminal and shell environment?
I spend most of my time working in Unix environments and using Terminal emulators. I try to use color on the command-line, because color makes the output more useful and intuitive.
What are some good ...
7
votes
2answers
250 views
Command line prediction
I've found an interesting paper: Predicting UNIX Command Lines about command-line prediction (based on user past activity), and I wonder if any actual implementation of such thing exists?
4
votes
2answers
42 views
Passing glob expressions to functions/scripts
The following script is supposed to concatenate multiple csv files in a path specified in the first argument into a single csv file specified in the second argument
#!/bin/zsh
set -x
set -v
...
9
votes
4answers
226 views
Why do I have to re-set env vars in tmux when I re-attach?
I mainly work on a mac and ssh/tmux attach to a Linux machine to do my work. I have ssh-agent running on the Linux machine. I have
set -g update-environment "SSH_AUTH_SOCK SSH_ASKPASS WINDOWID ...
6
votes
2answers
213 views
How do I add network or user source connection data to history entries?
I would like to modify the history settings for all users on the systems that I manage.
I would like it to contain the information from the connecting terminal like from who
sysadmin:/ # who
sysadmin ...
6
votes
4answers
271 views
How to make `cd dir/filename` take me to dir/?
I would find it very convenient to be able to use cd with a file argument.
cd myDirectory/anyname.anyExtension
would be equivalent to
cd myDirectory/
What would be the best alias or function to ...
0
votes
2answers
36 views
TAB autocomplete on sudo sh
When I say sudo sh, TAB stops working as autocomplete signal on my Debian.
How can I enable TAB key autocomplete after I say sudo sh ?
13
votes
2answers
2k views
ls command: what does the first line mean?
I haven't been able to find this through internet, when I do ls -l I get this:
calico@A000505:~/Documentos$ ls -l
total 2020
-rwxr-xr-x 1 calico calico 8559 2010-11-16 11:12 a.out
-rwxrw-rw- 1 smt ...
0
votes
0answers
43 views
unexpected bash behaviour after console login (openSUSE)
I'm trying to install a Linux OS on the computer I use as a home server, because I liked "Raspbian" so much on my Raspberry Pi. I created a custom linux using openSUSE Studio, that's just text based ...
0
votes
0answers
18 views
Getting “zsh: command not found: time” when running `time` in subshell
I installed ZSH (and Oh-My-ZSH) on a Ubuntu 12.10 64 bit machine a few days ago. I just tried to do:
time (time ls)
and got this error:
zsh: command not found: time
( time ls; ) 0.00s user 0.00s ...
2
votes
2answers
56 views
Linux listing files between two date without touch command
I need a command which will list the files between given date and time (YYYYMMDDHHMMSS - format) in to a text file.
I don want to use touch command as its creating permission issue.
I am new to this ...
0
votes
1answer
113 views
Converting update-rc.d redis_6379 defaults to chkconfig command
I'm trying to run the commmand below to Centos and of course I get command not found. How do I then convert it to chkconfig ?
update-rc.d redis_6379 defaults
3
votes
3answers
118 views
Concatenating thousands of files: > vs >>
I found two seemingly contradictory answers on StackOverflow to the following questions:
Concatenating Thousands of Text Files Across Hundreds of Directories (while keeping some structure)
How do I ...
3
votes
1answer
42 views
Can't indent heredoc to match nesting's indent
If there's a "First World Problems" for scripting, this would be it. Mainly asking because I feel like I should know how to get around it if I need to.
I have the following code in a script I'm ...
9
votes
1answer
229 views
How do you set up the environment for es?
I've been playing with es the last couple of days, and it (like rc) has the quirk/feature that it only runs its startup script (.esrc) on login. The usual way to run code in each interactive session ...
1
vote
3answers
63 views
How to know which is the default script shell in Centos?
I'm using Centos 6 and after reading about different shells and dash implementasion as sh replacement in Debian, Ubuntu and Fedora, made up my mind to replace sh with dash as the script shell in ...
17
votes
2answers
529 views
Command line: <<< instead of <<
Why is the command md5sum <<< 'ddd'
(output: d6d88f2e50080b9602da53dac1102762 -)
right, and md5sum << 'ddd' not?
What does <<< mean?
7
votes
3answers
5k views
What does ` (backquote/backtick) mean in bash?
I came across the following command
sudo chown `id -u` /somedir
And I wonder what is the meaning of the ` symbol. I noticed for instance that while the command above works well the one below does ...
6
votes
4answers
2k views
Number of files containing a given string
How can I count the number of files (in a directory) containing a given string as input in bash/sh?
0
votes
1answer
133 views
Send email if specified files do not exist
I am new to unix scripting. I have to do something like :
In a folder /x everyday 10Pm and next day 3 AM, 2 files are placed. I have to write a script which will check the folder /x and confirm if ...
232
votes
4answers
41k views
What is the exact difference between a 'terminal', a 'shell', a 'tty' and a 'console'?
I think these terms almost refer to the same thing, when used loosely:
terminal
shell
tty
console
What exactly do each of these terms refer to?
3
votes
2answers
193 views
What is Linux for OpenVMS DCL Ctrl/T?
From OpenVMS DCL Dictionary:
The Ctrl/T function displays a single line of statistical information
about the current process. When you press Ctrl/T during an interactive
terminal session, it ...
1
vote
1answer
23 views
How to open all the files in a directory, using terminal, in emacs?
I've 4 java files in a directory, which I want to work with in emacs. How do I open them all together? Thanks
23
votes
10answers
5k views
Get exit status of process that's piped to another
I have two processes foo and bar, connected with a pipe:
$ foo | bar
bar always exits 0; I'm interested in the exit code of foo. Is there any way to get at it?
16
votes
5answers
926 views
In what situations would a user not let the shell record his command into history?
If I add export HISTCONTROL=ignorespace in .bashrc, bash won't record any commands which have whitespace before them into history. But I do not understand under what situations it will be useful. ...
2
votes
3answers
45 views
Log in with specific shell at terminal login
If I log in to a system over ssh, I can use the default shell with a simple ssh user@host, or specify something like ssh user@host 'bash --norc --noprofile' or ssh user@host ksh.
Is it possible to ...
1
vote
2answers
69 views
What does the tilde (~) mean at the end of a filename? [duplicate]
What is the file with the ~ at the end of the filename for?
$ ls # aliased to add flags
-rwxrwxr-x 1 durrantm 2741 May 16 09:28 strip_out_rspec_prep_cmds.sh~*
drwxrwxr-x 13 durrantm 4096 May 16 ...
3
votes
3answers
34 views
Print process ID (PID) of a Matlab instance
To run my Matlab scripts, I've created a shell script to which I give two parameters - the path to the matlab file ($1) and to the log file ($2):
nohup time matlab -some_parameters -r "run $1;exit" ...
0
votes
1answer
35 views
List partitions in grub2 shell?
I've been doing some spring cleaning of my hard drive. This cleaning caused my grub configuration to get messed up ( no surprise there ). So when I boot I wind up in the grub2 shell. ( The shell with ...
0
votes
2answers
46 views
At init, run my own script instead of the shell
This is purely theoretical but suppose I would like to deploy a linux distribution on many servers. The only solution I can think of would be to create an initramfs with a custom script to perform ...
0
votes
1answer
27 views
Weird behavior when sourcing .zshrc
I'm using zsh 5.0.2 (x86_64-apple-darwin12.3.0) on the latest MacOSX. If it makes any difference, I have also enabled oh-my-zsh.
The shell seems to be missing the .zshrc file when I want to source ...
18
votes
5answers
5k views
How to test what shell I am using in a terminal?
How to check what shell I am using in a terminal? What is the shell I am using in MacOS?
1
vote
3answers
80 views
sed - how to replace a single quote?
This works fine:
sed -i 's# @driver.find_element(:xpath, "//a\[contains(@href,##' temp_spec.rb
against a source of
@driver.find_element(:xpath, "//a[contains(@href,'change_district')]").click
...
1
vote
1answer
40 views
gunzip multiple compressed files to another directory without deleting the .gz files
I have multiple .gz file in a folder and I want to unzip it in other folder through gunzip without deleting parent file. Please help.
0
votes
2answers
71 views
Is there a general command to see what shell is running? [duplicate]
On some the shell can be read on in the command prompt, other can be seen when help is ran. But this are not covered by all the shells.
Is there a general command to see what shell is running?
4
votes
4answers
110 views
sed how to substitute when string has “http://” in it?
I have a file xx that has the following contents:
@base_url = "http://dmstaffing-stage.herokuapp.com/"
I want to use sed to eliminate this line (replace with nothing). I have used this sed ...
3
votes
0answers
56 views
Fork vs. thread system time [closed]
I got the following logs:
Program 1:
Taken from a program executed 64 fork calls:
real 0m0.023s
user 0m0.068s
sys 0m0.008s
Program 2:
Taken from a program executed 64 thread calls:
real 0m0.613s
...
1
vote
5answers
1k views
bash execute read command from file
After some manipulations, I got the file with commands that I would be glad to be able to execute.
Input file (name of file is inp2.txt):
"02 - Beautiful Emptiness.mp3"
"02 - Come. mp3"
"02 - Go ...
34
votes
6answers
24k views
How to split the terminal into more than one “view”?
From vi, if you issue the command :sp, the screen splits into two "views", allowing you to edit more than one file from the same terminal.
Along those same lines, is there a way to have multiple ...
3
votes
1answer
31 views
Ignore files for zsh's completion for SVN
I managed to configure zsh such that it does not suggest LaTeX temporary files when I use autocompletion for emacs by adding this line to my ~/.zshrc:
zstyle ':completion:*:*:emacs:*:*files' ...
0
votes
1answer
68 views
Why does my TCSH prompt change after cd?
My .cshrc file contains the following:
set prompt = "%{\033[0;32m%}%S%B\! <%~> :%b%s %{\033[0m%}"
Each time I cd out of my home directory, the prompt formatting resets to display:
33 ...
3
votes
6answers
178 views
How do I specify arguments to return all dot files, but not . and ..?
Normally dot files are not included for wildcard expansion:
% echo *
Applications Desktop Documents Downloads Library Movies Music Pictures Public bin
If I explicitly ask for dot files, I get them:
...
4
votes
3answers
739 views
shell script to read from multiple files in parallel
I need to write a script that runs parallel and looks for a string in multiple files. I tried a lot of options but they slow down the speed of my processor.
2
votes
1answer
216 views
Xubuntu 12.04: slow login
I'm running Xubuntu 12.04, and after I ran the update, my login started slowing down big time. I've dabbled a little bit with the programs in Settings -> Settings Manager -> Session and Startup, and ...
75
votes
13answers
10k views
How to do integer & float calculations, in bash or other languages?
Using echo "20+5" literally produces 20+5
What command can I use to get the actual sum, e.g. 25 in this case.
Also, what's the easiest way to do it just using bash for floating point, e.g.
echo ...
3
votes
3answers
95 views
How to move all files with a certain file extension from subdirectories to a single directory
I have a directory that contains many subdirectories. The subdirectories contain lots of types of files with different file extensions. I want to move (not copy) all the files of one type into a new ...
3
votes
1answer
74 views
How can I keep color codes with grep input?
It I grep something twice:
... | grep foo | grep bar
It seems foo is not highlighted.
Infact, it seems grep removes colorcodes from its input; Any way to prevent this?
1
vote
2answers
54 views
Reduce redundant logfile
I often have longer redundant log files, redundant in the sense that blocks of text repeat with minor changes. The length of the files makes it difficult to spot the actual information. I had the idea ...
1
vote
4answers
249 views
linux shell global linux memory in mem variable - from shell
Is there any way for me to set an env variable without editing files to be in memory and effect other shells as well, which will take effect on any new user who connects that machine and will take ...
