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Questions tagged [pipe]

Pipes or named pipes are a feature of the POSIX standard that allow separate processes to communicate with each other without having been designed explicitly to work together.

Pipes or named pipes are a feature of the POSIX standard that allow separate processes to communicate with each other without having been designed explicitly to work together.

Pipe can also refer to the character produced by pressing shift+backspace. It looks like this: |

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Getting colored results when using a pipe from grep to less

I use the --colour option of grep a lot, but I often use less as well. How can I pipe grep results to less and still preserve the coloring. (Or is that possible?) grep "search-string" -R * --colour | less EDIT: I'm looking for a direct solution…
Jeremy Powell
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Preserve colors while piping to tee

ls -l --color=auto | tee output.log Without pipe/tee it's colored. How can I make it so that it stays colored while using tee (can be colored only on the screen, I don't care about colors in logs).
Paweł Gościcki
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How to pipe command output to other commands?

Example: ls | echo prints nothing ( a blank line, actually ). I'd expect it to print a list of files. ls | grep 'foo', on the other hand, works as expected ( prints files with 'foo' in their name ). What I do in these situations is something like: …
Mihai Rotaru
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How can I save the current contents of less to a file?

If I've piped the results of a command to less and then decided that I want to save the contents to a file, is this possible? I've tried setting a mark a at the end of the buffer, and then returning to the top and using |avi to send the whole…
Jonathan Day
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How to suppress cUrl's progress meter when redirecting the output?

I'm trying to print just the verbose sections of a cURL request (which are sent to stderr) from the bash shell. But when I redirect stdout like this: curl -v http://somehost/somepage > /dev/null Some sort of results table appears in the middle of…
Ian Mackinnon
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Why is piping 'dd' through gzip so much faster than a direct copy?

I wanted to backup a path from a computer in my network to another computer in the same network over a 100 Mbit/s line. For this I did dd if=/local/path of=/remote/path/in/local/network/backup.img which gave me a very low network transfer speed of…
Foo Bar
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How to rate-limit a pipe under linux?

Is there a filter which I could use to rate-limit a pipe on linux? If this exists, let call it rate-limit, I want to be able to type in a terminal something like cat /dev/urandom | rate-limit 3 -k | foo in order to send a a stream of random bytes…
Frédéric Grosshans
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Can I use pipe output as a shell script argument?

Suppose I have a bash shell script called Myscript.sh that need one argument as input. But I want the content of the text file called text.txt to be that argument. I have tried this but it does not work: cat text.txt | ./Myscript.sh Is there a way…
Narin
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Why does Powershell silently convert a string array with one item to a string

Consider the following Powershell script, which searches for folders in C:\ with a 'og' in their name: PS C:\> (ls | %{$_.Name} | ?{$_.Contains("og")}) PerfLogs Program Files setup.log Now I narrow down the search to get only one item: PS C:\>…
Jonas Sourlier
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Bash: create anonymous fifo

We all know mkfifo and pipelines. The first one creates a named pipe, thus one has to select a name, most likely with mktemp and later remember to unlink. The other creates an anonymous pipe, no hassle with names and removal, but the ends of the…
Adrian Panasiuk
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Pipe to less but keep the highlighting

Is it possible to pipe output (e.g. dmesg) to a command like less (or equivalent) and keep the text highlighting used by the original command? example: on the left dmesg | less on the right dmesg
apoc
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Is there any way to keep text passed to head, tail, less, etc. to be colored?

Is there any way to keep colorization of text passed through pipe | to head, tail, less, etc.?
Timofey Gorshkov
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What is the general consensus on "Useless use of cat"?

When I pipe multiple unix commands such as grep, sed, tr etc. I tend to specify the input file that is being processed using cat. So something like cat file | grep ... | awk ... | sed ... . But recently after a couple of comments left on my answers…
arunkumar
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Find what process is on the other end of a pipe

I'm trying to trace some odd behavior of a few processes and ran into a point I'm not sure how to trace past. The hung process, which I attached to using strace -p showed this: Process 7926 attached - interrupt to quit read(3, Okay, so it's…
FatalError
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Comments in a multi-line bash command

This single-command BASH script file is difficult to understand, so I want to write a comment for each of the actions: echo 'foo' \ | sed 's/d/a/' \ | sed 's/e/b/' \ | sed 's/f/c/' \ > myfile (sed is just an example, actually it is a mix of…
Nicolas Raoul
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