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[UDUNITS #BUK-910616]: ut_get_name() returning NULL?

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  • Subject: [UDUNITS #BUK-910616]: ut_get_name() returning NULL?
  • Date: Thu, 25 Jun 2015 10:12:15 -0600
David,

ut_get_name(ut_get_unit_by_name(theUnitSystem, "pound") returns NULL because 
"theUnitSystem" is the SI system of units, which doesn't have a "pound".

I know it seems like you should recover the name. I had to take some shortcuts 
in order to keep the development time down and this was one of the sacrifices.

> Hi Steve,
> 
> I am having a problem with the ut_get_name() function not returning the
> name sometimes.
> If I do:
> 
> theUnitsSystem = ut_read_xml( NULL );
> unit1 = ut_get_unit_by_name( theUnitsSystem, "kilogram" );
> if( !unit1 ) {
> printf( "***** ut_get_unit_by_name for \"kilogram\" returned NULL\n" );
> } else {
> printf( "ut_get_unit_by_name( \"kilogram\" ) returned \"%s\"\n", ut_get_name( 
> unit1, UT_ASCII ) );
> }
> unit2 = ut_get_unit_by_name( theUnitsSystem, "pound" );
> if( !unit2 ) {
> printf( "***** ut_get_unit_by_name for \"pound\" returned NULL\n" );
> } else {
> printf( "ut_get_unit_by_name( \"pound\" ) returned \"%s\" (ASCII)\n", 
> ut_get_name( unit2, UT_ASCII ) );
> printf( "ut_get_unit_by_name( \"pound\" ) returned \"%s\" (LATIN1)\n", 
> ut_get_name( unit2, UT_LATIN1 ) );
> printf( "ut_get_unit_by_name( \"pound\" ) returned \"%s\" (UTF8)\n", 
> ut_get_name( unit2, UT_UTF8 ) );
> printf( "ut_get_unit_by_name( \"pound\" ) returned \"%s\"\n", ut_get_symbol( 
> unit2, UT_ASCII ) );
> printf( "ut_get_unit_by_name( \"pound\" ) returned \"%s\"\n", ut_get_symbol( 
> unit2, UT_LATIN1 ) );
> printf( "ut_get_unit_by_name( \"pound\" ) returned \"%s\"\n", ut_get_symbol( 
> unit2, UT_UTF8 ) );
> }
> 
> The output I get is:
> 
> ut_get_unit_by_name( "kilogram" ) returned "kilogram"
> ut_get_unit_by_name( "pound" ) returned "(null)" (ASCII)
> ut_get_unit_by_name( "pound" ) returned "(null)" (LATIN1)
> ut_get_unit_by_name( "pound" ) returned "(null)" (UTF8)
> ut_get_unit_by_name( "pound" ) returned "(null)"
> ut_get_unit_by_name( "pound" ) returned "(null)"
> ut_get_unit_by_name( "pound" ) returned "(null)"
> 
> If I can get the unit by name, why can I not get the unit's name for pounds?
> 
> Thanks,
> David


Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: BUK-910616
Department: Support UDUNITS
Priority: Normal
Status: Closed