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Questions tagged [perl]

Perl is a powerful, high level programming language. Questions about Perl should be limited to the Perl development environment, running Perl, or using Perl to automate tasks on your computer.

505 questions
209
votes
18 answers

Removing ANSI color codes from text stream

Examining the output from perl -e 'use Term::ANSIColor; print color "white"; print "ABC\n"; print color "reset";' in a text editor (e.g., vi) shows the following: ^[[37mABC ^[[0m How would one remove the ANSI color codes from the output file? I…
user001
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85
votes
11 answers

When to use Bash and when to use Perl/Python/Ruby?

We are doing all our scripting with Bash so far, but I'm starting to feel a bit silly about it. While we can of course do everything we want with Bash (it's quite powerful), I'm starting to wonder if we shouldn't use a proper scripting language (in…
futlib
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38
votes
5 answers

How to cut a file to a given size under Linux?

I want to shrink a file's size by brute-force, that is, I don't care about the rest, I just want to cut the file, say by half, and discard the rest. The first thing that comes to mind is Perl's truncate. I'm following the example on that page and…
xpt
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12 answers

How do I remove a file in Linux whose name looks like it's ONLY a hyphen, as in "-"

I've tried rm -- - rm "-" rm "\-" rm \- Gave Perl a shot ~$ perl -e '$junk = glob("-"); chomp $junk; print "$junk\n"; `rm $junk`;' - rm: cannot remove `-': No such file or directory ...and... ~$ perl -e '$junk = glob("-"); chomp $junk; print…
jgrundstad
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29
votes
5 answers

Can I use perl regular expressions in the vim command line?

I want to use perl regular expressions on the vim command line. For example, to capitalize the words on the current line, you could type: :s/(\w+)/\u$1/g
user51549
  • 391
23
votes
3 answers

Command vs program?

I was looking up the difference between adduser and useradd, and an explanation is that useradd is a command while adduser is a perl script. I understand what a perl script is, but what I do not understand is what a command then exactly is. I always…
kramer65
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20
votes
8 answers

How do I queue multiple files for copying on a Mac?

When I copy multiple files on a Mac, the system tries to copy them all at the same time. The problem is two-fold. First of all, when you select multiple files and copy them, they all go into one process with an "all or nothing" approach not unlike…
Kebman
  • 525
18
votes
7 answers

unix - split a huge .gz file by line

I'm sure someone has had the below need, what is a quick way of splitting a huge .gz file by line? The underlying text file has 120million rows. I don't have enough disk space to gunzip the entire file at once so I was wondering if someone knows of…
toop
  • 365
14
votes
2 answers

How can I identify non-ASCII characters from the shell?

Is there a simple way to print all non-ASCII characters and the line numbers on which they occur in a file using a command line utility such as grep, awk, perl, etc? I want to change the encoding of a text file from UTF-8 to ASCII, but before doing…
user001
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13
votes
3 answers

Getting the process id for current perl script

How do I get the process id for the perl process that's running the current script? getppid() doesn't return the same pid as ps -ea| grep . Is there is an easy way or do I just run the ps -ea command within my script and trim off the other pieces…
ageis23
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11
votes
1 answer

Perl for matching with regular expressions in Terminal?

I'm trying to familiarize myself a little with Perl to use for regular expression searches in Terminal (Mac). Now, I'm not really looking to learn Perl rigourously, just trying to find out how to do some simple regular expressions. But I can't…
Anders Svensson
  • 339
10
votes
1 answer

Counting occurrences in first column of a file

We have this file: 1 2 1 3 1 2 3 3 52 1 52 300 and 1000 more. I want to count the number of times each value occurs in the first column. 1 3 3 1 52 2 This means we saw 1 three times. How can I do that, in Perl, AWK or Bash?
Arash
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10
votes
7 answers

How to convert .xlsx to .txt?

I want to know if there is a Linux tool or a script available to convert .xlsx file to .txt.
user53032
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10
votes
3 answers

Why does a Perl CGI program not write to files on Fedora 40 with Apache?

Last week, I upgraded my Linux file server from Fedora 39 to Fedora 40, and several CGI applications written in Perl stopped working. I first noticed it when Foswiki could not show any pages, because it was unable to open its log file. After…
Lars Poulsen
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9
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3 answers

How to execute a PL file in Linux?

I have a vmware-install.pl file that I need to execute. I double click it but Linux will open it in a text editor for editing. How to execute this file? Can it be done from GUI? In file's properties says "allow executing file as program". I have…
GoUkraineGo
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