31
votes
Is it possible to implement a "name" booking system using linux file permissions
What you ask for the directory /reservations is exactly how the standard /tmp directory behaves:
Every user can create files in there and only he is allowed to delete or modify them. This is achieved ...
- 13.3k
19
votes
Accepted
How do I carry my variables from a Bash script into a Perl one?
Making variables available to child process in shell script can be done either by exporting variables
export foo=bar
Or by calling program with variables prepended
foo=bar ./my_prog.pl
In either ...
- 105k
17
votes
Accepted
How can I change ^L code in many files in Ubuntu?
Control-L (represented as ^L) is the "form feed" character. In ASCII, it has decimal value 12 (L is the 12th letter of the alphabet) or hex value 0c:
$ printf 'foo\x0cbar\n' | cat -et
foo^Lbar$
$ ...
- 136k
16
votes
How do I install asciiquarium?
No compiling is required as there is a PPA that I believe is run by a Debian developer dedicated solely to asciiquarium. Open a Terminal window and paste the following two commands:
sudo add-apt-...
- 38.1k
12
votes
Unable to find ack in Ubuntu 17.10 repositories
Ack has a test failure in Ubuntu 17.10 Artful and it has been excluded from Ubuntu until it passes. Perl is upgraded on Artful and the old ack version isn't supported by the new Perl. The new version ...
- 4,150
11
votes
Accepted
How do I install asciiquarium?
These instructions will work for Ubuntu 12.04 and later.
Install term-animation
First, you need to install Perl module called term-animation. Open a command-line terminal by pressing CTRL+ALT+T.
...
- 1,094
10
votes
Accepted
Ubuntu 15.10 Installing SDL2
Easiest way is to just install by apt-get...
If you just want the libraries:
sudo apt-get install libsdl2-2.0
On Bionic or newer:
sudo apt-get install libsdl2-2.0-0
If you want to do development:...
- 326
10
votes
Accepted
What's the difference between the different "rename" commands?
How come there are two packages providing different commands using the same name (if not by accident)?
That's not unusual. Authors typically pick the simplest command name they think of, so if two ...
- 198k
10
votes
How do I carry my variables from a Bash script into a Perl one?
Using the environment is a cleaner way.
There is the -s switch:
$ cat vars.pl
#!perl
use feature 'say';
say "foo=$foo";
say "bar=$bar";
$ echo "$foo,$bar"
123,456
$ perl -s ./vars.pl -foo="$foo" ...
- 17.9k
9
votes
Trying to update from 16.04LTS to 18.04LTS but unmet perl dependencies or conflicts when updating packages
@user535733: you're the man! it helped.
To be precise: you can't remove virtual package (which perl-modules are) - instead:
apt remove perl-modules-5.22
In my case.
- 91
8
votes
Cannot load cgi-library into perl-cgi-script
Partially answering this for my own archiving. This seems to be a recent error that stems from a broken dependency. I got a similar error message when check the error log.
tail -100 /var/log/apache2/...
- 181
8
votes
How to replace the content to multiple files?
With awk you can just use | as column separator and print the first column:
awk -F '|' '{print $1}' file1.txt file2.txt file3.txt
output will be concatenaded. If it's necessary to keep output in ...
- 105k
7
votes
Accepted
process over records of files based on timestamp in x interval of the time
Writing reports on time stamped datafiles; complex requirements
While the original question was a bit complicated, the context of the question made it a quite difficult one. Additional circumstances ...
- 83.8k
7
votes
Accepted
Deleted /usr/share/perl/5.26 because I had /usr/share/perl/5.26.1 folder
You have to simply use the power of APT to restore folder contents:
sudo apt-get install --reinstall \
$(dpkg -S /usr/share/perl/5.26 | sed "s/,//g" | sed "s|: /usr/share/perl/5.26||&...
- 100k
7
votes
Accepted
bash --> perl command: print only the replaced text
The -p argument is like sed's default print - also like sed, if you want to suppress default print, you would use -n instead.
So you could do
perl -ne "print if s/^Val2 = '(.*)'/\1/" test....
- 136k
6
votes
Accepted
How to compare 2 files and extract the particular sequence using ID in first file and print the out put
You could write a script to do this directly, but I suggest you use the two little scripts below instead. I have spent many years working with this sort of data and they have been very, very useful. ...
- 101k
6
votes
Unable to find ack in Ubuntu 17.10 repositories
Sadly ack is not in 17.10 repositories. A workaround is to install it manually as per the instructions on its website.
Here's what I did:
$ sudo su
# curl https://beyondgrep.com/ack-2.18-single-file ...
- 261
6
votes
Deleted /usr/share/perl/5.26 because I had /usr/share/perl/5.26.1 folder
Many programs/libraries use symlinks to abstract away the exact version numbers and present a more stable location. For instance, rarely do programs care that your Perl patch number is 5.26.1 but may ...
- 1,826
6
votes
bash perl \z doesn't work
The command line option -p means that the file is processed line by line, i.e. what you do is basically:
while (<>) {
s/text2\n\z/text3/s;
print $_
}
Therefore the \z does not match ...
- 1,616
5
votes
Accepted
Perl Cannot Find Module XML/Simple
All of the Simple.pm files you've found belong to other Perl libraries. None of them do what you want. You have found
IPC::System::Simple
Lintian::Command::Simple
Log::Message::Simple
Locale::...
- 36.5k
5
votes
Accepted
adding zero to specific location of file names
Use this command
rename -n -v 's/(.{4})(.*)/${1}0${2}/' *
See if the result is what you want, remove -n and -v options.
Explanation:
take this simple command:
rename 's/pattern/result/' filename(...
- 4,408
5
votes
Vim refuses to start with "error while loading shared libraries: libperl.so.5.14" after upgrade to Ubuntu 14.04
Just create a shortcut:
ln -s /usr/lib/x86_64-linux-gnu/libperl.so.5.20 /usr/lib/x86_64-linux-gnu/libperl.so.5.14
- 51
5
votes
echo first group in perl
Turn Perl's autosplit on. It splits the lines into the array @F (on whitespace), so $F[0] contains the first column.
ps -ejH | perl -a -E 'if (/bash/) {say $F[0]; last;}'
You can also get rid of the ...
- 13.3k
5
votes
Add minutes to date time column
I'm assuming that the last field should be interpreted in the same fashion as the penultimate one i.e. 340 means an offset of 3 hours and 40 minutes.
If that is correct, then using GNU awk's Time ...
- 136k
5
votes
Renaming multiple files by removing a single number (1 & 2) in each file
You can use mmv (install it with sudo apt install mmv) as follows:
mmv -n 'paired_dat_*2_R2*' 'paired_dat_#1\1_R2#2'
-n is used so that you can preview the changes without applying them to your files....
- 14.6k
4
votes
Perl .pl file downloads instead of being executed
Waking the dead but with the answer.
Do this:
ln -s /etc/apache2/mods-available/cgid.load /etc/apache2/mods-enabled/
ln -s /etc/apache2/mods-available/cgid.conf /etc/apache2/mods-enabled/
sudo ...
- 41
4
votes
Accepted
How to run a perl script with arguments
-- is commonly used to indicate end of options, in this case
perl -- file.pl -ARGUMENT
This is explained in the documentation
A -- signals the end of options and disables further option
...
- 431
4
votes
Accepted
How to ignore multiple files and directories with grive?
Ignoring multiple directories can be done by using positive lookahead.
This regex ignores the directories "irrelevant" and "unnecessary":
grive --ignore '(?=^irrelevant$)|(?=^unnecessary$)'
The dry-...
- 56
4
votes
I have a file. I need to print all the quantities with unique values no duplicates, using perl
Since you tagged your question perl, how about using a perl hash?
$ perl -ne '/[,|](38=\d+)/ ; print unless $seen{ $1 }++' file
Order:167342,9=205|21=1|553=2453|49=11342|56=MBT|10=085|55=/GCQ3|1=...
- 136k
Only top scored, non community-wiki answers of a minimum length are eligible