Questions tagged [tee]
tee is a command line utility that reads the standard input and writes to the standard output as well as a file specified as an argument. Use this tag for questions about the tee command.
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Can I use tee to display output that other utilities tend to suppress?
The macos pbcopy utility grabs its input stream and stores it in the system clipboard, without displaying anything. So, when I want to copy/paste the output of a command in the terminal, I typically ...
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What is the `tee` command in Linux?
I am trying to interpret the following tee command:
cat colors.txt words.txt | tee colorsAndWords.txt | wc
Is my understanding, as follows, correct?
cat colors.txt words.txt: This command ...
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tee /dev/stderr inside script truncates output file if you redirect stderr
Given a script like below if I try to redirect stderr to a file, then the file is truncated at the point tee is used:
$ cat test.sh
#!/bin/bash
set -eux
echo before
echo '{ "foo": "...
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How can I encode a plaintext configuration file then `tee` it into its destination?
I have a vanilla configuration for Nginx (nginx.conf) in plaintext format. It has Latin characters, space indents and is ~250 lines total. I use it when I compile Nginx from source. After the source ...
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Piping output to tee breaks the conditional
I am trying to test for the presence of custom firewall-rules on servers. I am doing this by processing the iptables output with awk and returning an appropriate exit-code. This works as intended, and ...
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66
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Breaking command output into new lines instead of refreshing the same line
I'm trying to write a script that involves SnapRAID, where the progress output of snapraid sync is timestamped and logged to both a file and stdout. The issue I am facing is that snapraid sync outputs ...
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21
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Mail remote commands output on failure
I would like to run a command on a remote server and send an email alert (locally) in case of failure. As surprising it is this actually works:
ssh -p1222 [email protected] 'cd /root/chk; md5sum -c /root/...
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Shell: Why is there a "duplicate process " on using a pipe and tee?
I'm not very familiar with bash process, and was surprised to see a "duplicate" process running while using pipe and tee. Can you help me understand this?
In the following, the path to the ...
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71
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shell stdout to two command and program is stuck
I have a sample shell command to calculate array percentile number
$ time zcat input.txt.gz | head -n 999999 | awk 'BEGIN{FS="\t"}{print $13}' | st
--percentile=97.5
75
real 0m3.532s
...
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68
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Using recursive grep on multiple group of words, and output them in different text files
I try to figure out a way to use recursive grep on a group of words, and output the results in different textfiles.
My thought was I can do this in my case:
grep -r -A 2 -B 2 --include={LIST}.{txt,log}...
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525
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Redirect output to one file, while simultaneously filtering output to another using grep
I have a process running that spits out a line of data every second. I want to output all the output to 'output.txt', but also output lines that have @ to a different file 'emails.txt'. I tried ...
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how to exit command without using ctrl + d
I want to open three terminals and I want to write a command in the first window that will send a Hello message to the other two. The command must allow a one-time sending without a response from the ...
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212
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Tee remove chars from file and not the console output
I want to output a command's results to both the console and a file. For that, I use tee. But I would also like to remove the ESC character from the file and not from the console output because it ...
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How to solve 'tee: Too many open files' when trying to redirect output to multiple files
I need to download hundreds of json files from a list of urls stored in a csv.
As it would be impossible to do so manually, I wrote a short bash script to read the urls one by one using Python and ...
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1
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217
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Trying to rotate logs however tee command fails to return after execution
My logs nohup.out is owned by root user while I m trying to rotate the logs using system which has privileged access using sudo
I have written the below script to rotate logs.
cat rotatelog.sh
cp /var/...
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2
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130
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Replicate tee behaviour without subshell usage so that variable scope is not affected
I need the capture the output of a command group in BASH to STDOUT and a log file. Consider this code with command grouping and it's output
#!/usr/bin/bash
main(){
declare -i mycode=1
echo "...
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Using sudo tee in script sends junk to terminal also, bash Debian 11 [duplicate]
I have a command line:
# Download and add the Nginx GPG key to verify the authenticity of the packages.
wget -O - https://nginx.org/keys/nginx_signing.key | sudo gpg --dearmor | sudo tee /usr/share/...
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1
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636
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tee is faster than no tee
I have this simple bash script:
#!/bin/bash
for i in {1..1000000}
do
echo "hello ${i}"
done
That prints a message a million times.
I try to compare the performance of dumping all the ...
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Why does the exec redirection disturb / interrupt a pipe to jq? [duplicate]
This is the reduced version of my script:
# parse json
echo '[{"foo":"bar"}]' | jq
# log output to file and stdout
exec &> >(tee -a "/tmp/test.log")
# parse ...
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181
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Clean way to print command used to run script (stdin), stdout and stderr into file
I was attempting to run a script in bash: cc.sh
To run the bash script:
../cc.sh ../seq/ seqf
where ../seq/ and seqf are both arguments required.
I wanted to save the command I used to run the script ...
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256
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Run 2 Commands, append to file & show command output on console, but of only one command
I am attempting to run a Linux command such as nmap & pass the input into the txt2html command which then appends to a file but also show the output of the nmap command only. The command provided ...
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How does tee differ from redirecting/appending?
If we want to copy-paste what we just wrote in stdin to stdout, we can use a redirect > or append >>.
How does tee also writing from stdin to stdout different?
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Why does `echo 'hi' | tee > a b c` create multiple files, whereas `echo 'hi' > a b c` doesn't?
My env: zsh, macOS
Command in concern:
echo 'hi' | tee > a b c
echo 'hi' > a b c
Command 1 creates files named a, b and c with content hi.
Command 2 creates a file named a with content hi b c....
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269
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Fork stdin to stdout & stderr?
I am wondering if it's possible to fork standard input to stdout & stderr? Something like this,
$ echo "hi" | fork > std.out 2> std.err
$ cat std.out
hi
$ cat std.err
hi
Or, am I ...
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2
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How to use tee to append to start of file, as opposed to last?
I'm using this bash command to append data to a markdown file:
echo "${{ env.PR_TITLE }}" | tee -a page1.md.
I was wondering if I could append the echo statement to page1.md at the start, so ...
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654
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How to get color in terminal but no color in output file [duplicate]
To show output in both terminal and to a file, tee can be used like below
ls --color=auto | tee opfile
But now, there is no color in the terminal. If I force colors, opfile also has colors which ...
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2>&1 | tee cannot get full output log
I'm using the timeout command to call my application in timeout duration. And I also use 2>&1 | tee to write the log in my application to a log.txt file.
The command: timeout 20 my_application ...
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leave color in stdout but remove from tee
I want to see color output when in stdout to the console, but I want to remove it in a captured copy of the output from the tee command.
In my case,
command_that_writes_color_to_stdout | tee file
I'd ...
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3
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exporting global variable in tee process substitution subshells [closed]
command | tee >(var="$(command1)") >(var1="$(command2)")
echo "$var $var1"
Also tried moreutils pee
command | pee 'var="$(command)"' 'var1="$(...
user414574
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573
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get count of lines while in pipe
i have a bash script that looks like this:
some_process | sort -u | other_process >> some_file
I'd like to get the line count to while i'm streaming the data, after the data is sorted but ...
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Why does 'ping' not output a summary when redirecting output?
I can ping google.com for several seconds and when I press Ctrl + C, a brief summary is displayed at the bottom:
$ ping google.com
PING google.com (74.125.131.113) 56(84) bytes of data.
64 bytes from ...
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tee iso contents into dd or directly to /dev/sda?
Over a year back, I contributed to a tutorial on how to install NixOS on Linode.
It seems like most tutorials that deal with putting iso files on installation media always use dd, which is why "...
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How to split a stream to two binaries with retry?
I have a binary that produces an audio stream in s16le format. I want to split this stream to two different processes, but I don't want the command to exit and interrupt process 1 if process 2 errors. ...
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740
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Get hash from file while you copy or move it
Say I copy a file with pv, is there any way to also get any hash, like md5, sha1, etc without having to read origin twice? It has to work with big files or block devices.
Example command which does ...
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580
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How might I direct the output of "wget -qO- whatever.tar.gz" to both tar and sha256sum?
The following creates csfile with a hash in it, unpacks go1.17.4.linux-amd64.tar.gz downloaded from Golang's official website,
prints out the checksum to stdout and then removes the no longer needed ...
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52
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Piping JShell REPL through tee
If possible, I would like to pipe JShell REPL through tee in the following manner:
jshell | tee "~\jshell-`date +'%d_%m_%Y__%H-%M-%S'`.log"
The command executes and Shell launches but no ...
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1
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555
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tee in for loop not working as expected
I'm trying to use tee in a for loop as such:
for ea in $(ls *bam)
do samtools mpileup -f $ref $ea | \
tee \
>(java -jar $varscan2 mpileup2indel --output-vcf 1 > vcf/"$(echo $ea | sed ...
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2
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Can we use $PIPESTATUS with the tee (or pee) command?
In my bash scripts, I often use pipes and would like to know which stage of the pipe was causing the problem in case of errors. The basic structure of such snippets is:
#!/bin/bash
ProduceCommand 2&...
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Is there a way to send all shell script output to both the terminal and a logfile, *plus* any text entered by the user?
I want to send output of a shell script, including user-entered text, to the terminal and a logfile.
I thought some combination of tee and exec might do it, but I’ve had no luck so far. I know tee by ...
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BASH 4: tee to log file, fail over to /dev/null
I have a script that attempts to log its actions. There's a single tee in there that does all of this. Currently, when the $LOG_FILE cannot be written to the script dies. Instead, I would like it to ...
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Can named pipes/FIFOs be used in a "cyclic" manner together with `tee`?
Why does the last line in this script gets stuck?
#!/usr/bin/env bash
trap 'rm -f numbers' EXIT
mkfifo numbers
decrement() {
while read -r number; do
echo "debug: $number" >&...
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Userspace solution to use store data and create a UDP server
I'm trying to come up with a good way manage an intermittently connected device that I'm using for a research project. It's a sensor that goes in and out of the water. While under water, of course, ...
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What's wrong with this branched data flow using `tee`, fifos, and `paste`?
In the spirit of this question, I want to create a branched data flow from a single source:
cmd1 ──> tee ──────────────> │
├─────> cmd2 ─────> │ cmd4
└─────&...
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bash grep in a tee
I am trying to write a log file and output to a console at the same time The below works well. However I have a sleep timer and the logfile counts down each second and fills the log. The "...
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How to redirect a command's `stdin` as well as `stdout` to the output
Suppose I have the Python script:
#!/usr/bin/env python
input('Y/n: ')
print('Next line')
After I press Y, I want both the terminal and my output.txt containing:
Y/n: Y
Next line
Running the ...
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Having the output printed on the screen and redirected to a file and forwarded the errors to another file
I’m trying to answer this lab question. Is there a way to solve this without using tee command?
As user1 on server1, run the ls command on /etc, /dvd, and /var. Have the output printed on the screen ...
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4
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Pipe result to multiple commands without writing on screen
I have a very big zip file (~10 GB) which I want to unzip, and the result has to be passed to two commands. The results of both subsequent commands have to be appended to a file, and
Currently, I run
...
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825
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why does tee refuse to work when launched remotely via ssh?
Where is my error? As an answer to a Stackexchange question, I tar a directory and transfer the archive to a remote system, where tee both deposits in a file and pipes it to tar for unpacking.
My ...
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Get the output of a remote ssh to local
I'm able to get the output of a failing lp command from a remotehost to my local script like below:
until ssh -q root@remotehost 'lp -d Brother_HL_L2350DW_series /root/moht/Printed/`basename "$...
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How to uncompress a gzipped partition image and dd it directly to the destination partition without writing to current partition?
I've backed up a partition using sudo dd bs=8M if=/dev/sda2 | gzip > /someFolderOnSDB/sda2.img.gz.
The image is stored on a separate disk sdb.
When restoring it using gunzip -k /mnt/bkp/sda2.img.gz ...
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