AT_C( ) searches the second character expression for the first occurrence of the first character expression. It then returns an integer indicating the position of the first character in the character expression found. If the character expression isn't found, AT_C( ) returns 0.
AT_C( ) is designed for expressions containing double-byte characters. If the expression contains only single-byte characters, AT_C( ) is equivalent to AT( ).
The search performed by AT_C( ) is case-sensitive. To perform a search that isn't case-sensitive, use ATCC( ).
This function is useful for manipulating double-byte character sets for languages such as Hiragana and Katakana.