[fpc-pascal] SetCodePage in older FPC 3.0.4

[Michael Van Canneyt]

On Wed, 29 May 2019, Tomas Hajny wrote:

> On 2019-05-29 12:19, Michael Van Canneyt wrote:
>> On Wed, 29 May 2019, Michael Van Canneyt wrote:
>>> On Wed, 29 May 2019, AlexeyT wrote:
>>> 
>>>>> FPC generally uses system library functions for the conversion, so 
>>>>> it
>>>> does not depend on the FPC version.
>>>> 
>>>> But FPC has such files. Are they used in SetCodePage code?
>>>> 
>>>> user at PC:~/fpcupdeluxe/fpcsrc/packages/rtl-unicode/src/inc$ ls cp*
>>>> cp895.pas  cp932.pas  cp936.pas  cp949.pas  cp950.pas cpbuildu.pp
>>>> 
>>>> and
>>>> 
>>>> user at PC:~/fpcupdeluxe/fpcsrc/rtl/ucmaps$ ls
>>> 
>>> These files are not used, they predate the fpWidestring unit, they are 
>>> for the
>>> charset unit, which can be used to manually convert codepages.
>> 
>> Correction: if you use the fpwidestring unit, these charset units are 
>> used.
>
> Well, I believe that it's still a bit imprecise. ;-) My understanding is 
> that a programmer deciding to use fpwidestring may decide on the set of 
> character mappings to be supported out of the box in his program. That 
> may be done in two ways. One is by including a unit for a particular 
> character set (e.g. fpcsrc/rtl/charmaps/cp1252.pas or 
> fpcsrc/packages/rtl-unicode/src/inc/cp932.pas) or a set of character 
> sets (fpcsrc/rtl/charmaps/cpall.pas and/or 
> fpcsrc/packages/rtl-unicode/src/inc/cpbuildu.pas) in the uses clause of 
> one of the project source files. The other is by loading a binary file 
> (install/unicode/charset/*.bcm) dynamically at runtime 
> (LoadBinaryUnicodeMapping in fpcsrc/rtl/inc/charset.pp). Both the units 
> and the binary files are generated from the *.txt files using tools 
> included with FPC.

Yes. See
https://www.freepascal.org/docs-html/current/rtl/fpwidestring/index.html

Michael.