• curTask — the current task index. This value should be less than or equal to nSteps, if specified, or less than or equal to the nSteps value passed to the most recent call to progressbar_start_job().

• taskLabel — a short description of the current step. If the empty string is specified, the step label field is left unchanged. This is the default. To specify an empty step label, use a single space (" ").

• nTasks — the number of known steps in the current job. The known number of steps may change during the course of a job — using this parameter allows programs to update the number of steps as the job progresses. A negative value leaves the number of steps reflected by the progress bar unchanged. A value of 0 puts the progress bar into indeterminate, or waiting, mode.