tai64nlocal reads lines from stdin. If a line does not begin with @, tai64nlocal writes it to stdout
without change. If a line begins with @, tai64nlocal looks for a timestamp after the @, in the format
printed by tai64n(8), and writes the line to stdout with the timestamp converted to local time in ISO
format: YYYY-MM-DD HH:MM:SS.SSSSSSSSS.
For example, in the US/Pacific time zone, the input line
@4000000037c219bf2ef02e94 mark
should be printed as
1999-08-23 21:03:43.787492500 mark
Beware, however, that the current implementation of tai64nlocal relies on the UNIX localtime library
routine to find the local time. Some localtime implementations use a broken time scale that does not
account for leap seconds. On systems that use the Olson tz library (with an up-to-date leap-second
table), you can fix this problem by setting your time zone to, e.g, right/US/Pacific instead of
US/Pacific.
Beware also that most localtime implementations are not Y2038-compliant.
tai64nlocal does not allocate any memory after it starts, except possibly inside localtime.