// Self Upgrading Script by Cron Stardust based upon work by Markov Brodsky and Jippen Faddoul.  If this code is used, this header line MUST be kept.
upgrade() {
    //Get the name of the script
    string self = llGetScriptName();
    
    string basename = self;
    
    // If there is a space in the name, find out if it's a copy number and correct the basename.
    if (llSubStringIndex(self, " ") >= 0) {
        // Get the section of the string that would match this RegEx: /[ ][0-9]+$/
        integer start = 2; // If there IS a version tail it will have a minimum of 2 characters.
        string tail = llGetSubString(self, llStringLength(self) - start, -1);
        while (llGetSubString(tail, 0, 0) != " ") {
            start++;
            tail = llGetSubString(self, llStringLength(self) - start, -1);
        }
        
        // If the tail is a positive, non-zero number then it's a version code to be removed from the basename.
        if ((integer)tail > 0) {
            basename = llGetSubString(self, 0, -llStringLength(tail) - 1);
        }
    }
    
    // Remove all other like named scripts.
    integer n = llGetInventoryNumber(INVENTORY_SCRIPT);
    while (n-- > 0) {
        string item = llGetInventoryName(INVENTORY_SCRIPT, n);
        
        // Remove scripts with same name (except myself, of course)
        if (item != self && 0 == llSubStringIndex(item, basename)) {
            llRemoveInventory(item);
        }
    }
}

default {
    state_entry() {
        upgrade();
        // rest of your script's startup code
    }
}