Questions tagged [streams]
In computer networking, STREAMS is the native framework in Unix System V for implementing character devices.
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How to remove unneeded languages from video files using ffmpeg?
I have a number of video files (500+) with lots of audio and subtitle streams for languages that I don't need and would thus like to remove to conserve storage space.
I tinkered around with ffmpeg, ...
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Is there a program that concatenates non-seekable streams (size not known in advance) and can separate them again?
I'm trying to concatenate multiple input files/streams into one stream (using the imaginary command stream-cat), pipe that stream into ssh and on the remote host separate it back into individual files/...
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Why is appending different streams to a file safe?
It's well known that redirecting standard output and error to the same file with cmd >out_err.txt 2>out_err.txt can lead to loss of data, as per the example below:
work:/tmp$ touch file.txt
work:...
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Stream Audio over LAN, Linux -> Windows, Debian 8
Tried ping between computer's static IP's connected by router (General failure).
Therefore UDP direct connection attempts went nowhere.
Tried using ffplay and pulse to stream audio, but Debian 8 is ...
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What would be the stream for file descriptor 3u?
I know that the stream for file descriptor 2u is stderr. However, I'm not sure what the stream for file descriptor 3u would be and why? Ultimately, what does 3u represent here?
user516609
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How to receive "v4l2-ctl --stream-to-host" stream from a machine on the same LAN on said host for use with, e.g., video conferencing software?
There is an example that streams a webcam to another computer by piping a V4L2 stream into netcat (v4l2-ctl --stream-to - | nc <host> <port>), and this works, but it feels redundant when ...
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What exactly is a single "atom" in a standard stream in linux?
Conceptually, a stream is a sequence of "characters" or "atoms", i.e. a binary stream is a sequence of 0s and 1s. But in Linux standard streams, if I write a bash script that asks &...
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Are there "non-standard" streams in Linux/Unix?
The so-called "standard streams" in Linux are stdin, stdout, and stderr. They must be called "standard" for a reason. Are there non-standard streams? Are those non-standard streams ...
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What would need to be changed to create a new standard stream?
Hopefully this question isn't too abstract, it touches on a bunch of software throughout the stack.
We all know about /dev/stdin, /dev/stdout, and /dev/stderr. What if I wanted to create a new ...
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bash I/O redirection - how to append to stderr
I have a script that loops over some big collection of data and performs some lenghty operations. Then i need to sort | uniq -c its output. So to let it know that its alive, I print a dot every N ...
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Spawn a terminal and redirect its stdout to original process
I'm trying to spawn a new terminal, execute a few commands and pipe their output to stdin of the original process. A mwe of what I'm trying to do is the following bash one-liner:
$ xterm -e sh -c &...
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dd bs=X count=1 reads less than X bytes [duplicate]
I have dd from GNU coreutils 8.32.
When I run { echo a; sleep 1; echo b; } | dd bs=4 count=1 then I get
a
0+1 records in
0+1 records out
2 bytes copied, 2.0381e-05 s, 98.1 kB/s
dd terminates during ...
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/dev/fd inconsistency
What explains the following inconsistency in the reported contents of /dev/fd?
erhannis@mnode6:/dev/fd$ ll /dev/fd/
total 0
dr-x------ 2 erhannis erhannis 0 Jan 12 22:10 .
dr-xr-xr-x 9 erhannis ...
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How to pipe all output streams to another process?
Take the following Bash script 3-output-writer.sh:
echo A >&1
echo B >&2
echo C >&3
Of course when ran as . 3-output-writer.sh it gets the error 3: Bad file descriptor, because ...
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Piping curl http://cheat.sh/python to less is showing strange ESC[38;5;246m [duplicate]
I am kinda new to Linux.
My base issue: I need to show the output of curl cheat.sh/python like a man or less page, so that I can easily scroll up and down.
What have I tried: curl cheat.sh/python | ...
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tar (child): : Cannot open: Is a directory
I know thats a pretty dumb question but I didn't found this precise question on internet
I try to tar -cvjf all the contents of a directory (/*) and directly redirect that to a file (> file) but ...
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Is there any control character or hack to prevent simple command line tools from showing subsequent data?
I'ld like to hide ugly data from being shown by command line tools like cat (and maybe simple text editors too) which often get confused by binary data. For example a VT100 terminal sometimes gets ...
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Proper (working) way to return an int pointer through STREAMS?
I had been doing some work with an old SVR4 box with serial i/o when I found that the driver for the serial card did not support TIOCMGET through an ioctl call (e.g. ioctl(fd, TIOCMGET, &arg);). ...
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What are two caveats of line buffering in Unix?
A paragraph from APUE Chapter 5.4 about line buffer:
Line buffered. In this case, the standard I/O library performs I/O when a newline character is encountered on input or output. This allows us ...
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Reading partially downloaded gzip with an offset
Let's say that there is one huge db.sql.gz of size 100GB available https://example.com/db/backups/db.sql.gz and the server supports range requests.
So instead of downloading the entire file, I ...
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Ffmpeg - youtube-dl
I have try to use ffmpeg to download youtube media in mp3.
ffmpeg -i <url> -f mp3 output.mp3
It's working with other urls, but not with youtube-dl retrived youtube video urls. Ffmpeg returns ...
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How to pass multiple files in one stream to process them pipe-like (without saving) on the receiving side?
I need to determine the filetype on an indeterminate number of base64-encoded filestreams coming from stdin (image files base64-encoded and cat'ed).
A single file would simply be ... | base64 -d | ...
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Stream raminication with continuation if one branch breaks
Say I ramify a video stream to 2 ffplay processes
cat video.mp4 | tee >(ffplay -i -) >(ffplay -i -) > /dev/null
Now, if I kill one of the ffplay process, the stream is stopped which is not ...
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Why were STREAMS marked obsolescent in POSIX.1-2008? [closed]
The POSIX.1-2008 XRAT rationale states that X/Open STREAMS may be removed from future versions of the standard, and that strictly conforming applications shouldn't use them, but it doesn't explain why....
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piping text file to telnet over ssh
I would like to pipe a text file with commands to a telnet session I have open on a ssh client, Is this possible?
an example:
I have a text file cmds that contains commands like
FirstFunction(A,B,C,...
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How to store endless stream to file?
Let's have any stream of binary data (like /dev/random, /dev/zero, etc.).
Let's have a file which size can be N at maximum.
Let's the N is in order of gigabytes.
Is there any elegant method/...
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How do pipes and infinite streams work?
I usually use command1 | command2 | command3 a lot in Linux but most of them are dealing with definite content.
When I tried this with an infinite stream cat | sed '' | sed '' which hopefully ...
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Watch not showing subshell output
Why does the following not output "hello" line?
watch bash -c 'echo hello'
As this one?
watch 'echo hello'
I expected to have echo write to bash output directly and this to be read by watch and ...
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How can I set up a "USB proxy" for /dev/ttyUSB0 over the network?
I have a device under test (DUT) and I measure its power usage the using a Power Analyzer Datalogger using the data from /dev/ttyUSB0.
The problem is that the DUT is now remotely from the workstation ...
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How to use sed to manipulate continuously streaming output?
I am putting together a presentation for a non-technical audience. I have a program running in bash that outputs a continuous stream of values, a few of which are important. I would like to highlight ...
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Remove data from the STDIN stream buffer of another TTY session
I encountered a problem the other day while running multiple tty sessions in separate terminal windows. I was running a expensive disk access command and was waiting for it to return. Meanwhile I was ...
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How I/O channels are implemented in Linux kernel?
stdin, stdout, stderr are some integers that index into a data structure which 'knows' which I/O channels are to be used for the process. I understand this data structure is unique to every process. ...
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How can I install STREAMS in Linux?
I searched on Google, but found nothing useful. I use SUSE now, how can I install LiS on my computer?
I'm hoping for a download link.
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