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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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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How/why does ssh output to tty when both stdout and stderr are redirected?
I've just noticed that
ssh user@host >/tmp/out 2>/tmp/err
can write something like
Warning the RAS host key...
...
Are you sure you want to continue connecting (yes/no)?
stdout and stderr ...
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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 can I pipe output of ffmpeg to ffplay?
How can I pipe the output of ffmpeg to ffplay?
At the moment I use a workaround in bash :
mkfifo spam
(ffplay spam 2> /dev/null &) ; capture /dev/stdout | ffmpeg -i - spam
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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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Is backwards redirection the same as a pipe?
In Linux if you type
sort < txtfile
is that the same thing as
cat txtfile | sort
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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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Pipe gunzip and mysql to gunzip a dump and import it
I have a .gz sql dump file (example: foo.sql.gz) that i want import in my database with the classic mysql command.
gunzip -c foo.sql.gz > foo.sql
mysql -uroot -ppassword foo < foo.sql
foo is ...
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How to pipeline stderr in cmd.exe?
Some programs would prefer to output the help message in stderr. I want to search the help message with grep command, xx /? | grep regex?
How could i do this?
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How can I pipe the output of *all* entered shell commands into another? (e.g. pipe everything into 'lolcat')
Good Afternoon,
(OS X user)
I am specifically trying to pipe the output of every shell command I type into the ruby gem 'lolcat' (which makes the output to the terminal rainbow colored).
Is there a ...
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How can I grep in source files for some text?
At the moment I'm using two commands, I'm sure there must be a better way...
wim@wim-acer:~/ffmpeg$ find . -name "*.h" -print0 | xargs -0 grep -i invalid\ preset
wim@wim-acer:~/ffmpeg$ find . -name "*...
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How can I both pipe and display output in Windows' command line?
I have a process I need to run within a batch file. This process produces some output. I need to both display this output to the screen and send (pipe) it to another program.
The bash method uses tee:...
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Piping with Process substitution and joining output again
I'm trying to make use of a powerful remote server in terms of video encoding.
I have a local DVD drive for ripping DVD to memory, finally residing in an mbuffer.
From there, I would like to split ...
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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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