gtk-tree-view-column-pack-start (column renderer &key expand)

column -- a gtk-tree-view-column object
renderer -- the gtk-cell-renderer object
expand -- true if the cell renderer is to be given extra space allocated to the tree view column

Packs the cell renderer into the beginning of the tree view column. If expand is false, then the cell renderer is allocated no more space than it needs. Any unused space is divided evenly between cell renderers for which expand is true.