* tchat   
 * lchat   
 * infile   (task-specific)
 * bgfile   (task-specific)
 * outfile  (task-specific)
 * multi    (task-specific)
 * multb    (task-specific)
 * addsubr  (task-specific)
 * addi     (task-specific)
 * addb     (task-specific)
 * docor    (task-specific)
 * emin     (task-specific)
 * emax     (task-specific)
 * err_mode (task-specific)