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.
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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 | ...
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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).
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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 ...
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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 ).
...
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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
...
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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....
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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 | ...
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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 ...
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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 ...
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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 ...
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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 ...
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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.?
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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
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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 ...
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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
...
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