function trim(str) { 
	sub(/^[ \t]*/,"",str); 
	sub(/[ \t]*$/,"",str); 
	return str
}

function string2pairs(pairs,str,   sep,   n,i,tmp) {
# generate list of booleans keyed by sub-strings of "str"
	n=split(str,tmp, (sep ? sep : ","));
	for(i=1;i<=n;i=i+2) pairs[tmp[i]]=tmp[i+1];
	return n;
}