The string "str1" (or as much of it as there is room for) is copied into the part of "str2" beginning at position "iposn$+$1". "iposn" is updated to indicate the end position of the copy of "str1" within "str2" after this operation. If no copying is done, "iposn" is returned unchanged.

void chrPutc( const char $\ast$str1, char $\ast$str2, size_t str2_length, size_t $\ast$iposn )

str1

str2

str2_length

$\ast$iposn