Questions tagged [pipe]
156 questions
0
votes
1 answer
How to display results without two first lines
When I run some bash command it returns 2 .. n lines of text (n is different each time, may contain blank lines).
How to filter the output to display the result skipping lines 1 and 2?
e.g.
$ my_command
file1
file2
file3
file3
$ my_command |…
![](../../users/profiles/36982.webp)
takeshin
- 1,431
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1 answer
Is there any limit to AIX 5.3 pipe size?
I'm in trouble while performing cat/tail/head operation on large files on Aix 5.3. When asking for a cat of several 1Go file redirected to another one:
cat file1 file2 file3 > outputfile
The outputfile is limited to 2Go (cat: output error and…
![](../../users/profiles/42395.webp)
snowflake
- 127
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0
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2 answers
how to check open ports of bunch of website at once with nmap/linux?
I want to use nmap in such a way that I could check bunch of server's port at once for checking whether their particular port is open or not?
right now I have 10 ip addresses but in future this could be more .
I know the very basic command in linux…
![](../../users/profiles/40693.webp)
Seyed Vahid Hashemi
- 207
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0
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1 answer
Does Apache spawn piped logger on each HTTP request?
I am examining a high-volume Apache prefork site and noticing that many log entries such as:
CustomLog '|/foo/bar/cronolog -foo -bar'
RewriteLog '|/foo/bar/cronolog -bar -foo'
When apache logs the request or the rewrite is cronolog spawned for EACH…
![](../../users/profiles/24452.webp)
Jé Queue
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0 answers
After piping Incoming mails to external script, mails are not shown in Inbox in iRedmail
I have been trying to pipe incoming mails to my python script which is just trying to read a mail and look for keywords and call api. But for some reasons my mails are not being delivered to my inbox. I am new to postfix and this is my first time…
![](../../users/profiles/978882.webp)
misscoder
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- 1
0
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1 answer
Pipe into command stored in bash variable
I enter two command in bash:
$export g='grep "something"'
$echo "something and another thing" | $g
But it doesn't work.
I want the second command to be evaluated by bash as : echo "something and another thing" | grep "something"
What should I do…
![](../../users/profiles/447069.webp)
rimalroshan
- 139
- 6
0
votes
1 answer
Why tail to same file create a empty file, or empty the file?
I try to maintain the last lines of a file, but when tail -n 10 test.txt > test.txt create or empty the file...
SO: Ubuntu server
Example:
#test.txt file 20 May 23 12:24 test.txt
a
a
a
a
a
a
a
a
a
a
use tail -n 10 test.txt > test.txt
new…
![](../../users/profiles/393058.webp)
DarckBlezzer
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0
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2 answers
how to extract a certain field from standard output with cut?
I have this output and want to extract the IMAGE ID from it
$ podman image ls | grep youtube-dl
localhost/youtube-dl latest 2d4e37c4d609 3 hours ago 205 MB
All I know piping this to cut -f3 should to this but doesn't. The…
![](../../users/profiles/474192.webp)
vrms
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0
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0 answers
Is it possible to trigger a 550 SMTP answer from a script Postfix piped a mail to?
I want to prevent backscatter from within a mailing list script that I use on my Postfix mail server.
Mail for a mailing list hosted there is piped to my script. At this point, Postfix can't know if the sender address is subscribed to the list, but…
![](../../users/profiles/203686.webp)
Tobias Leupold
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- 7
0
votes
2 answers
Piping nc to sed and evaluate datetime for each row
Could someone provide any idea, how could i pipe data from nc to sed (or awk, or anything) and evaluate and write to file a timestamp after each row?
What i have:
# cat /etc/systemd/system/ncserver.service
[Unit]
Description=netcat…
![](../../users/profiles/626428.webp)
M.Ch.
- 3
- 1
0
votes
1 answer
How can wireshark.exe on windows read from a pcap file stream?
This is probably less a wireshark question and more a "how do I pipe a file into an application" on windows.
On linux, I can capture a pcap file on another host with tcpdump and pipe it back to wireshark on the local machine for a live capture…
![](../../users/profiles/519518.webp)
I grok it
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0
votes
1 answer
Linux shell: Pipe stderr and stdout to one file AND to individual files at the same time (using tee?)
I would like to form a pipe-stream that captures stdout to one file and stderr to another file AND both in a third file (so also the complete terminal output is in one file)
somehow like this:
process ----+-- --- + --- stdlog.txt
…
0
votes
1 answer
Linux does STDOUT | STDIN piping write data to disk?
I was planning on passing encryption keys to zfs load-key pool/set through stdin. The keys passed are generated by another program in HEX format and dataset is configured to have keylocation=prompt, keyformat=hex so the key can be passed through…
![](../../users/profiles/576260.webp)
The amateur programmer
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0
votes
2 answers
nethogs -t | awk '{print $0}' return no output
nethogs is a linux process bandwidth monitoring tool. https://github.com/raboof/nethogs
nethogs -t
it's output looks like this.
Refreshing:
sshd: root@pts/0/4002/0 0.185156 0.0773437
unknown TCP/0/0 0 0
Refreshing:
sshd:…
![](../../users/profiles/37899.webp)
The Unix Janitor
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0
votes
2 answers
Run a multiline bash script piped from stdin
I'm looking for a simple way to include multi-line scripts inline in documentation to make it transparent what each step does.
This works
echo "echo 1234" | bash
So does this
echo 'for N in 1 2 3; do echo $N; done' | bash
However, I'd like to use…
![](../../users/profiles/510408.webp)
Nanzikambe
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