Questions tagged [streams]
In computer networking, STREAMS is the native framework in Unix System V for implementing character devices.
26
questions
0
votes
0answers
28 views
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 &...
0
votes
1answer
53 views
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 ...
0
votes
0answers
8 views
how to count number of null bytes in stream? [duplicate]
i basically want find /dir -print0 | wc -0 , unfortunately wc doesn't have a 0/look-for-nulls argument; this works:
find /dir -print0 | php -r '$ret=0;while(!feof(STDIN)){$ret+=substr_count(...
0
votes
1answer
22 views
/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 ...
20
votes
3answers
18k views
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 ...
3
votes
0answers
146 views
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 ...
0
votes
0answers
14 views
Stream Video with Audio to a virtual device
I am able to write my video to virtual video device with the help of V4l2. Though video plays, audio is not available in the other end in Google meet. How to get stream audio of the video also.
I am ...
0
votes
0answers
28 views
plex media server running on debian check for ongoing streams in bash
How can I check on my debian server, if content is being used (streamed) by the plex media server? I want to know if someone is using the server and react to that.
Is there a way to find out via ...
4
votes
2answers
2k views
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 ...
2
votes
1answer
71 views
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 | ...
0
votes
1answer
660 views
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 ...
1
vote
0answers
28 views
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);). ...
3
votes
1answer
257 views
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 ...
3
votes
2answers
433 views
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 | ...
2
votes
2answers
359 views
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 ...
1
vote
1answer
1k views
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 ...
1
vote
1answer
28 views
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 ...
1
vote
1answer
1k views
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,...
3
votes
2answers
393 views
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....
2
votes
1answer
141 views
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/...
4
votes
3answers
2k views
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 ...
16
votes
4answers
11k views
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 ...
4
votes
1answer
881 views
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 ...
3
votes
2answers
1k views
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 ...
8
votes
2answers
7k views
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. ...
0
votes
1answer
2k views
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.
