pch_ptrn_lines
LINENUM pat_lines = pch_ptrn_lines() - fuzz;
LINENUM pat_lines = pch_ptrn_lines();
const LINENUM oldlast = oldfirst + pch_ptrn_lines() - 1;
pch_ptrn_lines() ? oldfirst : 0,
pch_ptrn_lines(), newfirst, pch_repl_lines());
const LINENUM lastline = pch_ptrn_lines();
LINENUM pch_ptrn_lines(void);