CHARSET_INFO.txt:

New comments about ctype[].
This commit is contained in:
bar@mysql.com 2004-10-21 15:11:01 +05:00
parent 636ddd4128
commit aec49dae4d

View file

@ -74,7 +74,16 @@ Conversion tables
ctype - pointer to array[257] of "type of characters" ctype - pointer to array[257] of "type of characters"
bit mask for each chatacter, e.g. if a bit mask for each chatacter, e.g. if a
character is a digit or a letter or a separator, etc. character is a digit or a letter or a separator, etc.
to_lower - pointer to arrat[256] used in LCASE()
Monty 2004-10-21:
If you look at the macros, we use ctype[(char)+1].
ctype[0] is traditionally in most ctype libraries
reserved for EOF (-1). The idea is that you can use
the result from fgetc() directly with ctype[]. As
we have to be compatible with external ctype[] versions,
it's better to do it the same way as they do...
to_lower - pointer to array[256] used in LCASE()
to_upper - pointer to array[256] used in UCASE() to_upper - pointer to array[256] used in UCASE()
sort_order - pointer to array[256] used for strings comparison sort_order - pointer to array[256] used for strings comparison