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Questions tagged [fifo]

Questions about FIFO - first-in first-out special file, also known named pipe

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Are FIFO, pipe & Unix domain socket the same thing in Linux kernel?

I heard that FIFOs are named pipes. And they have exactly the same semantics. On the other hand, I think Unix domain socket is quite similar to pipe (although I've never made use of it). So I wonder if they all refer to the same implementation in…
Justin
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Are the named pipe created by `mknod` and the FIFO created by `mkfifo` equivalent?

I've used the mkfifo command to create named FIFOs, where one process writes to the file, and another process reads from the file. Now, I know the mknod command is able to create named pipes. Are these named pipes equivalent to the FIFOs…
Shuzheng
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Prevent automatic EOFs to a named pipe, and send an EOF when I want it

I have a program that exits automatically upon reading an EOF in a given stream ( in the following case, stdin ). Now I want to make a shell script, which creates a named pipe and connect the program's stdin to it. Then the script writes to the pipe…
iBug
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Why is a named pipe as slow as writing to a file?

I'm trying to understand how named pipes work so that I can streamline my one-way interprocess communication. I expect some overhead due to copying data into a circular buffer, which I would have thought is stored in RAM, and so I expected the pipe…
Jim Pivarski
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continuous reading from named pipe (cat or tail -f)

I have configured rsyslog to log certain log events to /dev/xconsole: *.*;cron.!=info;mail.!=info |/dev/xconsole /dev/xconsole is a named pipe (fifo). If I want to see what is being logged, I can do cat /dev/xconsole. I am surprised to see,…
Martin Vegter
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A virtual file containing the concatenation of other files

Is there a way of creating a filesystem object akin to this: mknod files p cat file1 file2 ... fileN > files but such that it can be seeked in, as if it were a regular file?
Witiko
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How to get an average pipe flow speed

If myfile is increasing over time, I can get the number of line per second using tail -f | pv -lr > /dev/null It gives instantaneous speed, not average. How can I get the average speed (i.e the integral of the speed function v(t) over the…
user123456
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How do I use inotify or named pipes over SSHFS?

Thanks sshfs magic, I can mount my home dir from a remote server with sshfs user@server:/home/user ~/remote Optimistically, I thought I'd set a local inotify-hook on ~/remote/logFile (in the sshfs mount) so a local program can react to remote log…
Anko - inactive in protest
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How does a FIFO (named pipe) differs from a regular pipe (unnamed pipe)?

How does a FIFO (named pipe) differs from a regular pipe (|)? As I understand from Wikipedia, unlike a regular pipe, a FIFO pipe "keeps living" after the process has ended and can be deleted sometime afterwards. But if f the process is based on a…
Arcticooling
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“Leaky” pipes in linux

Let's assume you have a pipeline like the following: $ a | b If b stops processing stdin, after a while the pipe fills up, and writes, from a to its stdout, will block (until either b starts processing again or it dies). If I wanted to avoid this, I…
CAFxX
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Can you scp, sftp, or rsync, a pipe?

I want to tar and send a ~700GiB directory to a remote drive I don't control. I don't have the HDD space locally to create the tarball and then copy that over. The remote is also protected by rssh - you cannot ssh into the server and run arbitrary…
SaburoutaMishima
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Filter or pipe certain sections of a file

I have an input file with some sections the are demarcated with start and end tags, for example: line A line B @@inline-code-start line X line Y line Z @@inline-code-end line C line D I want to apply a transformation to this file such that lines…
James Scriven
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Under what conditions exactly does SIGPIPE happen?

Say we have a named pipe called fifo, and we're reading and writing to it from two different shells. Consider these two examples: shell 1$ echo foo > fifo shell 2$ cat fifo foo shell 1$ echo bar > fifo shell 1$ cat > fifo …
Naïm Favier
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Named pipes, file descriptors and EOF

Two windows, same user, with bash prompts. In window-1 type: $ mkfifo f; exec f Now window-1 prints an ls and then the…
Fixee
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Change buffer size of named pipe

I hear that for named pipes, writes that are smaller than about 512bytes are atomic (the writes won't interleave). Is there a way to increase that amount for a specific named pipe? something like: mkfifo mynamedpipe --buf=2500 Supposedly this is…
Alexander Mills
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