Questions tagged [cat]
A UNIX utility for concatenating files or input streams together. Do not use for questions about the animal.
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Tar & save the output of a command
I want to tar the output of a command, say cat hello.world, to a compressed tar file.
I don’t want to save a temporary file and later tar it manually.
How can I do this?
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Recover text file that I deleted with "cat" command
I used
cat > filename
while not thinking about it, then hit
ctrl + c and naturally enough the file is now empty... Is there a way to recover that file's contents?
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How to use the command "read" on a Shell script which reads its arguments from stdin
First of all, thank you for your help in advance and sorry in case this was answered before. I have not been able to find it.
For helping to understand my question, I have written the following ...
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vote
1
answer
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To print values in diferent line in mail body shell script
Below is the code to print contents of files present in the directory
File contents are :
apple
banana
grapes
mango
names=()
FILES=/path_to_dir/*
for f in $FILES
do
names+=($f)
done
...
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votes
1
answer
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Receiving data from Serial Port
I want to receive data from RS232 Serial port to my terminal and with a directive to a file. It should be pretty straight forward.
cat /dev/ttyS0
cat /dev/ttyS0 > file.txt
Before that I've ...
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vote
0
answers
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views
Cat playing with mouse broke my Windows/Explorer :( Cannot click buttons in most of standard apps/menus
My mouse was laying on a sofa (I was going to clean it a bit) and my cat suddenly decided to play with the mouse (while the start menu was opened). Nothing serious happened with it during these 10 ...
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Using wildcards with cat append target
I need to append the contents of two files to a third, where I don't know the exact file name of the target. Let's say it's named targetXXXXX where XXXXX is a random string. I am basically trying to ...
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2
answers
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pipe and stdin redirection to cat
Why does
echo "hello world" | cat
works while
cat < echo "hello world"
does not? My (incorrect) intuition is that pipe would redirect stdout to cat as stdin.
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2
answers
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shell - multiple text insertion into each line of a file
I have a text containing coordinates of points such as x, y and z, I would like to change each line to be like:
Point{ (1000+linenumber) } = {x , y, z};
What I want is: for example for line 212 ...
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1
answer
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views
/usr/bin/mail not interpreting new lines
I have a strange problem when piping a cat to mail.
I have a simple text file which has been compiled from a script, which is a report on what folders were copied in the script. I then want to send ...
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What's the behaviour of `cat | less`?
I tried to run the following command:
cat | less
I know both commands require something from the standard input.
When I run it that's what I expected: all my inputs goes to cat and I will not be ...
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vote
3
answers
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views
add new line after every end of file's contents while merging multiple files
I have written shell script to merge different file's contents I have created directories f1,f2,d1,d2 and files under them , I need to merge all files's contents : comand is
(find /home/ah5024331/f1 ...
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1
vote
1
answer
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views
Empty line appears while merging different file contents in shell script
I have written shell script to merge different file's contents I have created directories f1,f2,d1,d2 and files under them , I need to merge all files's contents : comand is
find /home/ah5024331/f1 /...
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views
Piping a line of the file read with while read loop
I am trying to read each line of the file and then assign some parts of it to variables. A line itself is read as a variable so I need to process a variable input say for cat which seems to be ...
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How to merge multiple files into single file in given directories
I want to write a shell script to merge contents of multiple files in a given directories.
DIR1 contains sample1.txt sample2.txt
sample1.txt contents :---this is sample1 file---
sample2.txt ...
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cat > $FILE_NAME << EOF - Explanation of the inner workings
I know what this one does, I learned "pattern like" and just works.
I also know:
that > is a redirect to a file
that << is also a redirect to file see below
EOF is just a placeholder, when ...
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votes
3
answers
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views
Using -replace on pipes in powershell
I want to test out a replace before I use it, so I'm trying to write a quick online command to see what the output is. However, I'm not sure what the syntax is. What I want to do is something like
...
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0
answers
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views
How to uninstall screen (monitor / display) drivers?
While testing out some different computer screens (also called displays or monitors) on a Windows 7 SP1 system, I installed the .INF files for each screen. I also installed the .ICM (color matching ...
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votes
4
answers
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views
Prevent cat from opening a binary file
Is there a way to prevent or prompt you when trying to cat binary files?
Oftentimes I need to work with log files or data files, some of which are text and others not. It's easy to get mixed up, and ...
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vote
2
answers
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views
Is cat output modified by writing to the file
With a piped command sequence like:
$ cat afile | somecommand | tee afile
afile is both read (by cat) and written (by tee).
The question is, supposing afile is at least several megabytes (or large ...
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2
answers
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views
Combine the results of a CAT and TAC in a single window in Linux
I have two log files which I would like to view on my screen simultaneously. Below you can see my commands:
pi@raspberrypi ~ $ watch -n 1 tac /home/pi/log/log.txt
pi@raspberrypi ~ $ watch -n 1 cat /...
user414196
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answers
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lossless concatenation of ogg vorbis files
I have a couple of ogg vorbis files, all encoded with the exact same properties that I want to concatenate into a single file.
I know that the ogg vorbis format supports plain concatenation of ...
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Unix cat to Windows user
I uploaded about 6GB of video in 3 separate files created using the cat command on my Mac, thinking the recipient of those files was a Mac user as well. It turns out he's using Windows 8. How can he ...
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linux cat into file including exiting code all from copy+paste
Can I print out a code to STDOUT that would mimic the behavior of Ctrl+c inside cat? E.g. I would like my script to print out the cat command followed by the content of the file like this:
cat > /...
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views
how to clone a directory list to another directory
I am trying clone a directory and it's subdirectories into another directory. I have hundreds of music directories with sub-directories that I want to convert from flac to ogg. I want all the music ...
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vote
2
answers
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views
Make a web request, cat response to stdout?
I'm working from the command line. I need to cat the response of a web request. What tool can I use to make the web request and print the response on stdout?
Here's the command I'm trying to make ...
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votes
2
answers
1k
views
Trying to cat the result of piped commands
I have a folder of files that are named list20140801.txt list20140802.txt ....
I'm trying to do this
ls | sort | tail -3 | cat
But it is just giving me the file names, not cat'ing them.
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views
Sort piped to uniq unexpected output
I have a file that looks like this:
"string",192.168.1.0,,TX,192.168.1.2,,,100,0,0,10,10,10,,
"string",192.168.1.0,,TX,192.168.1.1,,,100,0,0,10,10,10,,
"string",192.168.1.0,,TX,192.168.1.4,,,100,0,0,...
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views
Adding text to the end of multiple files, minus one line( Adding return 0; at the end of each program in C)
I have a bunch of C programs from K&R and of course, no return statement. I was wondering if there was a way to cat to the end of each file (except one line before the end, so EOF - 1) the ...
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votes
2
answers
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cat wc -l count lines line with defined line endings (e.g Mac OS X specific)
As any command-line user I sometimes want to count lines in text file with well known command:
cat some_text_file | wc -l
I face the problem on Mac OS X, which as far I have it studied is connected ...
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votes
4
answers
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views
Change Behavior of Linux Power Button
I have a headless linux mint machine that I use for a file server and other things. It's been working great for me for a few years, but there's one issue - my cat likes to hang out on top of it, and ...
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vote
1
answer
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head and cat don't recognize Microsoft Excel text files
I have a large .xls file with 53760 rows and 19 columns. I saved it as Tab Delimited Text in order to pre-process it through command line tools and load it into R later. However, when I run
head ...
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Execute a command for 3 lines at a time
I'm trying to run three separate processed while reading foo.txt
Here is the example:
cat foo.txt | while read line
do
echo line1
echo line2
echo line3
echo ""
done
The expected output is:
line1
...
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1
answer
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views
Can cat be used to clone a partition?
For example, can I do:
cat /dev/sda1 > /dev/sda2
instead of using dd, and if not, why will this not work?
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3
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Move multiple files from filename list to a new folder
I have a list of filename in list.txt, which have 'abc1.png, abc2.png, abc3.png....'.
However, I don't know the directories where the files are.
I want to find all files in the txt file, and move ...
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views
Special and diacritic charactres using less, cat and other linux tools
I am using GNU bash, Version 4.1.10(4)-release (i686-pc-cygwin) and set up my .inputrc to allow for special characters and German umlauts etc.:
set meta-flag on
set convert-meta off
set output-meta ...
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views
How to print statistics from lines in a file
I often find myself computing percentages manually after filtering through a log file to find the proportion of X or Y in it. Can this easily be achieved via common CLI tools?
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votes
2
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Why did my bash prompt turn to gibberish after I accidentally ran `cat` on a .coverage file?
I had just installed coverage and run it a few times when I noticed a .coverage file hanging around in my repo, which is -- according to the file utility -- a 8086 relocatable (Microsoft) file. And ...
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Why does echo work through pipe but not cat with msmtp?
This works:
echo "yada yada" | msmtp [email protected]
but not this:
cat yadayada.txt | msmtp [email protected]
which delivers the email with empty content.
Why does echo work through pipe but not cat ...
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Copying a template header to multiple existing files
I have a bunch of *.csv files that use headers. Right now the files have headers and the same number of lines of data. I need to erase the data in these files, so I figured I could just overwrite the ...
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votes
4
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How can I stop cat output immediately despite massive output?
I'm looking for someway to stop the output to STDOUT when I realize a command is wrong. For instance, if I accidentally cat a very large file. Usually it will eventually stop if you hold down ctrl + c,...
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4
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Is there anyway to `cat` two remote `tail -f` streams via SSH?
I wanted to combine two continuous text streams generated by tail -f into one and watch them in the same screen. Is it possible? Both text streams are line-oriented (e.g. logs), if that helps.
...
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votes
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answers
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Cannot cat file which has space in name in linux
I believe there's a simple fix but cannot debug it out.
I have file called "file name with space"
How do I cat this file from Linux bash ?
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How can I simplify this command in Linux consisting of cat piped to a grep?
How can I simplify this command in Linux consisting of cat piped to a grep.
cat foo*.txt | grep cow
I was told that this is the wrong way to do this. Why is that?
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how to copy entire linux root filesystem to new hard drive on with ssh and tar
I need to transfer an entire linux root filesystem off of a failing hard drive onto another computer with an open, available partition. I've pretty sure this involves tar and ssh, but I can't remember ...
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Write output to $TMPDIR/$variable : file does not exist (should be created)
I have the following .sh script in which I am trying to do all major writing in $TMPDIR.
However, when it gets to line 86, it returns the following error:
/var/spool/uge/bnbhimem2/job_scripts/855849:...
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How to prepend contents of a file to another
This question relates to the already asked question How to add text to beginning of file
The answer suggested by Dennis Williamson does the job:
echo 'task goes here' | cat - todo.txt > temp &...
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cat command outputs the whole directory when used in a bash script
I have a scirpt like this:
#!/bash/bin
file=`cat /proc/net/arp`
echo $file
And when I run the script it outputs the whole folder where the script is like this:
IP address HW type Flags HW address ...
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views
Combining multiple data files with header while also adding a data column
I have multiple tab delimited data files that are separated by month in the format jan06.txt, feb06.txt, ..., dec07.txt.
Within each file, it looks something like:
Header1 Header2 Header3 ...
Data1 ...
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How to display the file contents recursively?
I always have to submit the source codes in my printed assignment report. I have to copy and paste my course codes into the document and I find that it is an annoying task.
I want to solve this "copy ...
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