Error in datestr.m in Octave-3.2.0 MingW

[John W. Eaton]

On 22-Jun-2009, Philip Nienhuis wrote:

| Octave's function datestr.m fails for dates before Jan 2, 1970 in the
| MingW build 3.2.0:
| 
| **********************<screen copy:>*********************************
| 
| GNU Octave, version 3.2.0
| Copyright (C) 2009 John W. Eaton and others.
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| warning: mark_as_command is obsolete and will be removed from a future
| version of Octave
| octave-3.2.0 > datestr(datenum(1970, 1, 1))
| ans = 00-Jan-1900
| octave-3.2.0 > datestr(datenum(1970, 1, 2))
| ans = 02-Jan-1970
| octave-3.2.0 >
| 
| **********************</screen copy>*********************************
| 
| The previous 3.0.3 VC++ Windows build is OK in this respect.
| 
| I haven't checked other binary octave versions yet.
| 
| While perusing the source code of datestr.m I couldn't find the spot
| where the actual conversion takes place (but then again I'm neither an 
| octave nor a C++ guru).
| (Speculation (sorry): I suspect the use of strftime() may be related to 
| this.)

Yes, it uses strftime.  It seems to work for me on my Debian system:

  octave:1> datestr(datenum(1970, 1, 1))
  ans = 01-Jan-1970
  octave:2> datestr(datenum(1969, 1, 1))   
  ans = 01-Jan-1969
  octave:3> datestr(datenum(1929, 1, 1))
  ans = 01-Jan-1929

I guess strftime is broken on MinGW?  I think the proper place to fix
that is in the MinGW C library.

jwe