...
Notes
The string can be of the form HH(:)MM(:SS)(:CC). For example five to two might be represented as "13:54:43:04". The () are optional.
Related calls
GN_Gmt, get (read) machine time in internal format
GN_Msc, miscellaeneous time operations
GN_Pmt, put (set) machine time
GN_Ptm, write internal time as ASCII string
GN_Sdo, send date and time to standard output
OS_Dly, delay a given period