texlive import packages from older installations

Question

I've been using TeX Live 2018 and installed some packages to that, now that 2019 is out, I need to intall that new version (windows). I am using basis scheme install option (plain and latex) for normal reasons. Is it possible to like import 2018 packages, which are installed on my computer to 2019? Or idk, install them again but not manually like create a list or something?

Another sub question would be if it is possible to copy the packages to another computer, or copy the list of those packages and on other computer click on it and install them in 1 go.

Answer 1

I solved this as follows: After installation of the new distribution (both are now installed)

• Open old Tex Live command-line and type tlmgr list --only-installed > old.txt.
• Open new Tex Live command-line and type tlmgr list --only-installed > new.txt.

Now copy those 2 files into a same folder, then I wrote a little script in MATLAB, it is simple and it probably can also be written in any other language, here it is:

oldfile=fopen('old.txt');
oldtext=fread(oldfile,'*char')';
fclose(oldfile);
oldpackages=regexp(oldtext,'(?<=i )[\w\.\-]+(?=:)','match')';
clear oldfile oldtext

newfile=fopen('new.txt');
newtext=fread(newfile,'*char')';
fclose(newfile);
newpackages=regexp(newtext,'(?<=i )[\w\.\-]+(?=:)','match')';
clear newfile newtext

packagestoadd=strjoin(oldpackages(~ismember(oldpackages,newpackages)));
clear newpackages oldpackages

the packagestoadd variable now contains all names of packages, which are installed on the old distribution but not on the new one.

• Now go to the new TeX Live command-line again (you have to open it as admin if it is installed in a folder like Programm files though), type tlmgr install and copy the string from the mentioned variable right after this command.

Edit: I have wrote this script in C++ and compiled it, here is the code:

#include <set>
#include <regex>
#include <fstream>
using namespace std;

int main()
{
    regex re("^i ([\\w\\.\\-]+):");
    smatch match;
    string line;
    ifstream newFile("new.txt");
    set<string> newPackages;
    while (getline(newFile, line))
    {
        regex_search(line, match, re);
        newPackages.insert(match.str(1));
    }
    newFile.close();
    ifstream oldFile("old.txt");
    ofstream file("toadd.txt");
    while (getline(oldFile, line))
    {
        regex_search(line, match, re);
        if (newPackages.find(match.str(1)) == newPackages.end())
        {
            file << match.str(1) << endl;
        }
    }
    oldFile.close();
    file.close();
}

I have also compiled it for windows x64, you can use it without additional software. there is also a batch file, which then installs TeX Live packages automatically. I upload it here: C++ executable. To use it simply download, put in any folder on your PC, then let TeX Live command line create the 2 text files (must be named old.txt and new.txt) and put them into the same folder as the 2 downloaded files. Then simply double click on the bat file.

If you installed your TeX Live in the Programm Files folder, which needs admit permissions, you will need to run cmd or TeX Live command line as admin, navigate to the folder in which you copied the files (with cd command) and then type import texlive packages.bat.

If you just want to know the difference, you can double click on the exe file, it will only create a new text file containing the missing packages in new.txt.