Questions tagged [perl]
Perl is a high-level, general-purpose, interpreted, dynamic programming language. It was originally developed by Larry Wall as a general-purpose Unix scripting language to make report processing easier, over a period with support from open source community, it has evolved and matured to be used for graphics programming, system administration, network programming, finance, bioinformatics, and other engineering applications.
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How can UserA programmatically replace a text string within a file they own that's located in /etc?
A non-root linux user owns a text file that's located in /etc, where the non-root linux user does not have permission to create files. The non-root linux user can edit the file manually via vi without ...
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1
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What does the line ($eachJOBID = $eachScriptNoPath) =~ s/\.csh// ; do?
This line I have in my code cuts the .csh from a string and returns the rest of it. Can someone explain what each part of it does?
($eachJOBID = $eachScriptNoPath) =~ s/\.csh// ;
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Bash: sum a number present in N lines before a given pattern
I have a kdenlive project file (which is basically a xml file) with a lot of text clips inside. I need to bulk edit the x coordinate of a certain text that appears multiple times. This is an example:
...
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Why is one process ps command showing spaces around a directory instead of slashes?
I'm trying to debug a failing legacy process monitor that searches processes that are running. I determined it is being caused by some mysterious linux behavior. The process being ran is /opt/my/path/...
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how to catch output from a subprocess?
I am trying to catch the password prompt of sftp, but somehow it is not from STDIN or STDERR. It possibly comes from a sub-process.
The following is my test. I tried to redirect the password prompt to ...
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1
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AWStats stuck, but no output on strace: How to debug?
A Perl script is stuck,
root 1317478 99.8 0.0 264072 22516 ? R 04:57 478:37 /usr/bin/perl /usr/share/awstats/wwwroot/cgi-bin/awstats.pl -config=domain.tld-http -staticlinks -configdir=/...
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3
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awk: sort by first column then second; output unique 1st column once but all 2nd column
I have a two-column file that you can create as follows
cat > twocol << EOF
007 03
001 03
003 01
137 12
001 11
002 01
002 02
002 03
001 02
002 04
137 94
010 21
001 01
EOF
The resultant file, ...
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How to combine ...if $x and a here-doc in perl? [closed]
How is one supposed to write this?
print <<EOF; if $x
bla
EOF
I think it is called postfix notation, and a here-doc. I get a syntax error.
OK, I guess I'll just use
print "bla" if $x;
...
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7
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How can I print the longest sequence of lines featuring numbers smaller than a threshold?
I am learning Perl, but I don't know how to solve this problem.
I have a .txt file of the following form:
1 16.3346384
2 11.43483
3 1.19819
4 1.1113829
5 1.0953443
6 1.9458343
7 1.345645
8 1....
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How to use `perldoc` within Emacs (shell)?
While programming using Emacs, you frequently consult manual pages.
My environment is text-based Emacs via SSH.
While I can open "Normal" manual pages in Emacs using the man command ((man ...
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Search and replace content
PIN A
1 1:3 0:8
0 0:0
PIN B
1 1:0
0 0:0
Z Z:0
PIN C
1 1:3 0:8
0 0:0
Z Z:0
I would like to change the content on PIN A & PIN C only without affecting PIN B to
0 0:3
Z 0:3
Can't seem to find a ...
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1
answer
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Report sed changes + corresponding perl syntax
Newbie learning Linux and perl:
I would like to (a) search-replace strings, (b) match filename pattern .myfile., (c) look recursively in subdirectories, and (d) print the line number, file name, ...
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7
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Find all lines between two patterns, EXCLUSIVE of the second pattern?
Consider that I have the file listed below. I need to select all lines from every instance of the regex pattern Word A to before the regex pattern Word D.
Word A
Word B
Word C
Word D
Word E
Word F
...
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getting started with PDL for cluster analysis PDL::Stats::Kmeans
I guess first up is the Question " is perl data language dead ?" I'm not finding any active discussions or user q&a
sorry for not tagging this better I dont have the rep'
my problem area ...
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0
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Perl's `kill` is using `$! == Errno::EINTR` unexpectedly
I wrote a network daemon that forks off children to handle TCP connections.
On SIGINT the main process triggers a kill for each child in order to clean up and to collect some final statistics.
In ...
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