-1
votes
0answers
28 views

Practical usage of pushd, popd, man, less, and cat in bash [on hold]

So i am learning more advanced usages of bash/cmdline due to work teaching me some programming and im trying to wrap my head around some of the following bash cmd's and their purposes. I have been ...
1
vote
3answers
82 views

How to enter foo-* folder without actually using wildcard or shell expansions?

Short story I'm looking for the command to enter first found foo-something directory like: cd foo-* but without using wildcard (or other special shell characters). Long story As part of the ...
0
votes
1answer
67 views

How do I use vim on the command line to add text to the middle of a file?

I am trying to write a command along the lines of the following: vim -c "XXXXXX" myFile Instead of the "XXXXX" I want to supply some commands to vim to add some text to an arbitrary point in the ...
0
votes
3answers
71 views

Can dash replace bash as my default shell?

From what I read, dash can be made as a shell by using the command ~$ chsh shirish Password: Changing the login shell for shirish Enter the new value, or press ENTER for the default Login Shell ...
1
vote
2answers
27 views

Listing folder contents during cd command

I might be mistaken here, but I was watching someone navigate using the cd command, and without actually executing it, they were able to show the folder contents of the current folder. So if I type ...
16
votes
5answers
2k views

Why do I sometimes get repeatedly prompted with “>” in the terminal?

Alright, when I run certain commands the wrong way, (misspelled, etc.) The terminal outputs this: > instead of computername:workingfolder username$, and when I type enter it goes like this: > ...
0
votes
2answers
36 views

Add space after 8 characters then add space after every 4 characters

Here is the sample input: AbbigailAbieAbbyAbbi Using sed, I have separated them into 4 characters but seems like I got a problem because I have to separate the first 8 characters first then add ...
8
votes
4answers
472 views

How do I remove spaces from shell variables?

I have done the following at command line: $ text="name with space" $ echo $text name with space I am trying to use tr -d ' ' to remove the spaces and have a result of: namewithspace I've tried ...
5
votes
3answers
134 views

I am trying to find a better/easier way to count alphabetic characters in a file or shell variable

I have a file containing the following text: we are going to write something 1 2 3 wc tells me I have 1 line 9 words and 38 characters. I'm looking to count the 26 letters only (a-z, no numbers or ...
3
votes
3answers
208 views

Method for storing/remembering one liner commands

Often when configuring and adjusting unix-based systems I use a lot of one-line commands that are difficult to remember. For example, to determine what version of ntp (the time server) is running, you ...
1
vote
1answer
44 views

Is autocompletion for applications done by shell?

When I type evince, and then hit tab, the bash shell will list all files that can be opened by evince, which seems to be based on the ext part of the filename. Is this done by shell or the ...
1
vote
3answers
186 views

Execute a file if a command is not found

When I try to execute files in Linux, I'm always annoyed by the need to write ./executablefile instead of just executablefile. I get why it's done, so it won't have an ambigous input, one that is a ...
2
votes
1answer
72 views

How to sort files based on the json property value inside the file?

I've downloaded list of videos via youtube-dl and each file has corresponding .json file containing certain properties. So I would like to sort the files based on the selected json property which is ...
6
votes
2answers
189 views

How many commands can be queued up with control operators?

I have been reading up on control operators, and I was wondering if there was a limit to how many commands you could line up with control operators, such as ||, && and ;. In addition, is ...
1
vote
2answers
137 views

Pass a command to ROOT from a shell script and having it stay open

I am writing a bash script to perform some analysis using the program ROOT. I want to run some initial command to load the result of the analysis, then continue using ROOT interactively. The analysis ...
2
votes
2answers
45 views

Select a range of files after sorting them

One thing I notice slower for me if I switch from using a GUI file manager to CLI is: In a GUI file manager, I can quickly select a subset of files under a dir by, first sorting them according to ...
0
votes
1answer
44 views

Must pass urls in quotes

I'm trying pass a URL to mpv for it to play it as a network stream. This can be done in bash with the following syntax: $ mpv http://myvideosite.com However, zsh wants to evaluate the URL as ...
6
votes
2answers
320 views

How to find out which program can open a given file?

Let's say I have a file thesis.pdf or picture.jpg Is there a command which returns a program to open this file with? I am aware of the command file, but it just returns the correct type of the file ...
4
votes
3answers
228 views

Write text messages between Unix and Windows

Is it possible to send text messages between two users of the same LAN, but the first running Windows with cmd and the second running Linux/Unix? I am not looking for an instant messaging service. I ...
0
votes
0answers
14 views

command type “hashed”? [duplicate]

type displays information about a command's type. How would it be interpreted if used as a command name? What command "types" are there? In the following example, what does "hashed" mean? Is it ...
1
vote
3answers
107 views

Problem when splitting command with backslash in unix prompt

I often use the space-backslash combination ( ) to split a command and its parameters into various lines and make it more readable: /home/user> ls -ltra \ > file1.txt \ > file2.txt ...
3
votes
4answers
186 views

Generate random numbers in specific range

After googling a bit I couldn't find a simple way to generate with a shell command a random number included in a specific range, between a minimum and a maximum. I read about /dev/random, ...
5
votes
3answers
171 views

Combining brace expansion and output redirection

Often, I use parameter expansion on the command-line, such as cp a.{ext1,ext2} which is expands to cp a.ext1 a.ext2 However, in many cases I do not use cp, but another tool, let's call it cat, ...
1
vote
1answer
114 views

How to find list of available shells by command-line?

How to list available shells for use by command-line?
6
votes
1answer
99 views

Filetype and dereference when listing directory with LS command

I'm trying to combine arguments to the ls command to list a directory content. What I'm basically trying to achieve is listing the directory dereferencing all links, but showing explicitly that the ...
1
vote
5answers
143 views

How to copy a file from a remote network to the local desktop

So I used SSH to remotely login to another computer on a network. I have many files that I would like to copy over to my local desktop. I am trying to follow this How-to : However, I think one ...
10
votes
2answers
509 views

disable CTRL-D window close in terminator (terminal emulator)

I am often logged in through multiple SSH sessions. To logout from my sessions, I press CTRL+d, until I am back on my local machine. However, sometimes I press once too many, and my terminal exits. ...
7
votes
6answers
2k views

How to read first and last line from cat output?

I have text file. Task - get first and last line from file after $ cat file | grep -E "1|2|3|4" | commandtoprint $ cat file 1 2 3 4 5 Need this without cat output (only 1 and 5). ~$ cat file | ...
2
votes
2answers
138 views

“cat” command: how to automatically escape everything that might be a violation?

If you copy the contents of httpd.conf and then paste it into a cat command.. such as this one.. #!/bin/bash cat > /test << EOF pasted here.. EOF you run into this error: -bash: ...
8
votes
3answers
987 views

Local, timestamped logging of all ssh commands?

How can I keep a local, timestamped record of all remote commands I use in ssh (command-line openssh client started through bash)? Requirements: Essential: 100% client-side without relying on ...
1
vote
3answers
131 views

How to remove all FIFO files with a shell command

I can't find a shell command to remove all the FIFO files inside a directory. In fact, for the removal of directories, the rm command offers the options -d, --dir, but for FIFOs it offers no option. ...
0
votes
1answer
895 views

Proper escaping of double quotations for curl post data?

I'm trying to test out a server, by sending it JSON data and reading the response. I need to POST data like {"item":"value with spaces"} but when I use curl I find that it sends the backslashes as ...
1
vote
1answer
42 views

Is there a command which creates a temporary file containing the arguments passed to it?

I can paste the contents of a file into a command using cat and backticks: ls `cat filenames` Is there a way to do the reverse - to turn a string into a (temporary) filename? gcc -o cpuburn `uncat ...
0
votes
1answer
46 views

Set alias which doesn't send specified text? [closed]

EDIT I set a alias task in ~/.bashrc. The following: alias join="clear; screen -ls; screen -rx [<ID_OF_THE_RUNNING_SCREEN> quit]" If i the task join is executed, the following has to ...
3
votes
1answer
77 views

What is 'ls quote'?

Today I happened to press ' after ls So the command is ls' After I issued this command: [edit]Seems the image can't display properly > ls' quote> ls' zsh: command not found: ls\nls > ...
15
votes
3answers
2k views

Why isn't there any shell command to create files?

Attention please: I am not asking how to make a file from the command line! I have been using touch for making files for years without paying attention that its main purpose is something else. If ...
16
votes
6answers
2k views

Why do I have to cd out of a deleted directory?

On my server I have a directory structure looking something like this: /myproject/code I normally have an ssh connection to the server and 'stand' in that directory: root@machine:/myproject/code# ...
7
votes
3answers
497 views

What is the difference between the use of ; and executing a script

I'm using bash as my main shell, but it's an open question and responses for shells others than bash are very welcome. If I'm typing interactively #original line #wget http://something.com ...
8
votes
3answers
364 views

How to execute a command repeatedly with different arguments?

I'm on Ubuntu. I copied some arguments (separated by newline) and I can use xsel to print them out like this $ xsel arg1 arg2 arg3 arg4 ... Now, I want to use each of these arguments for another ...
1
vote
1answer
79 views

Command works with tilde at the end. How?

I'm on Ubuntu. I have a script called myscripts in /usr/bin/myscripts This script simply changes the current directory to ~/Work/MyScripts Normally, I simply open a terminal and type ~/Desktop$ . ...
1
vote
1answer
340 views

Exit of “> ” mode in Unix shell

In sh (not Bash), how would we abort execution of command when the prompt is in > mode? For example, when entering a string with quotes only at the beginning, it makes the prompt look like >, ...
1
vote
7answers
333 views

what are some uses of .(single period) & ..(double period) in the shell command line

The single period . means current working directory The double period .. means parent of the current working directory I can only think of . being used in relative pathname etc cd ./bin/usr How are ...
2
votes
1answer
291 views

When should you use subshells vs `xargs`?

Many simple commands using xargs could be rewritten as commands using subshells. For instance, here is something I was using earlier today, to concatenate the ten largest binaries in /usr/bin, written ...
2
votes
1answer
396 views

Copy files based on date/time from subset of directories

I'm teaching a class where (~80) students are submitting assignments that I can access via webdav, organized by student in directories named by their unique identifier. The students are split into ...
9
votes
2answers
572 views

How can I redirect `time` output and command output to the same pipe?

Suppose I have a binary called foo. If I want to redirect the output of foo to some other process bar, I could write ./foo | bar. On the other hand, if I wanted to time foo, and redirect the output ...
4
votes
2answers
254 views

Dump process's stdin and stdout

I have two processes, let's say Parent and Child. Parent launches the Child and communicates with it through child's stdin and stdout. Parent <-> Child These processes use text protocol and I ...
3
votes
7answers
492 views

Batch renaming of files [duplicate]

I have a directory full of images: DSCN4749.JPG DSCN4750.JPG DSCN4892.JPG ... And I would like a one-liner to rename them to (say). dscn4749.jpg dscn4750.jpg dscn4892.jpg ... How do I do this? ...
2
votes
4answers
250 views

Incrementing a variable each time the system boots up

The idea is to initialize a variable and set it to 0. Then create a script that executes on boot and increments that variable by 1 each time the system boots up again. Sounds simple enough right?
6
votes
5answers
911 views

How does one find out how many bits a file has in one command?

I know I can use ls -lat to find out how many bytes has a file and then multiply by 8 to find out how many bits. But is this possible in only one command line?
0
votes
1answer
234 views

How to escape spaces while using command's output in command line [duplicate]

I want to perform the following command in command line : $ md5sum $(find . -type f) But this would cause problems when it encounter files with spaces in filenames : md5sum: Kaufmann: No such ...