The ones I have removed used household type carpet tack strips around the edges. The prongs on these strips are always sharp and often very rusty. If you are not wanting the original carpet for a pattern, cut it about 6" from the edge and take the center out, then pull up the edges, then remove (very carefully) the rusty carpet tack strip.
Sometimes you will find the carpet has been put in first, then the cabinets put in over it. In that case you will need to cut around the edges to get the carpet to release.