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slackpkg-2.52-noarch-1 in extra/slackpkg
slackpkg  

slackpkg  is a package manager for Slackware. It can download,
upgrade, install and remove selected packages. With it, you
can search in the Slackware Package database and find which
package has the selected file.

slackpkg  DOESN'T replace pkgtool. Actually, slackpkg  uses pkgtool
for all install|upgrade|remove functions.