getify

function XYZ() {
   X();
}

function X() {
   // do X
   Y();
}

function Y() {

dive

# shutdown Skype
# Skype username - it's a login at Skype
# Mac username - it's a short username of Mac OS X (ex.: dive)
# <...> should be entered without brackets <>

#copy this one, paste to Terminal.app and hit Enter
sqlite3 "$HOME/Library/Application Support/Skype/<your_skype_username>/main.db"

#then copy this one, paste to Terminal.app where sqlite3 running and hit Enter
delete from Messages where dialog_partner = '<delete_history_of_conversation_with_particurarly_username>';