NAME CopyTuple -- Find/copy a credit card tuple. SYNOPSIS success = CopyTuple( CardHandle, buffer, tuplecode, size ); d0 a1 a0 d1 d0 BOOL CopyTuple( struct CardHandle *, UBYTE *, ULONG, ULONG ); FUNCTION This function scans credit-card memory for a tuple, and if found, copies it into a supplied buffer. The entire tuple (including the tuple code, and link) are copied to the supplied buffer. The number of bytes copied to the buffer will be 2 bytes, plus the argument "size", or the value in the tuple LINK field (whichever is SMALLER). The software calling this function is responsible for examining the copy of the tuple (e.g., recognition of fields, recognition of stop bytes, etc. within the tuple). This function does the best job it can to find a tuple in attribute, or common memory. It follows tuple chains, and skips odd bytes in attribute memory. This function monitors for credit-card removal while reading data. If the credit-card is removed while a byte is being read, it will stop searching, and return FALSE. This function does not protect against another task writing to credit-card memory while data is being read. The device is responsible for single-threading reads/writes to the credit card as needed. This function can be used to find multiple tuple codes; this is a very rare case, so the mechanism provided for doing so is unusual. See INPUTS below for more information. This function does not read bytes within the body of any tuples except for the tuple you want copied, and the basic compatibility tuples this function understands (see list below). On some machines this function may slow down memory access speed while reading the tuple chain. This is done to prevent potential problems on slow cards. By examining the CISTPL_DEVICE, and CISTPL_DEVICE_A tuples, you can determine the best possible memory access speed for the type of card inserted. Because memory access speed may be slowed down, calls to this function should be single-threaded. The Card Information Structure must start with a CISTPL_DEVICE tuple stored as the first tuple in attribute memory. If not, this function will search for a CISTPL_LINKTARGET tuple stored at byte 0 of common memory. Therefore it is possible to store a CIS on cards which do not have any writeable attribute memory, though this may cause problems for other software implemented on other machines. For example, some SRAM cards do not come with writeable attribute memory, and/or some may have OPTIONAL EEPROM memory which may not have been initialized by the card manufacturer. While it could be argued that such cards do not conform to the PCMCIA PC Card Standard, such cards are cheaper, and therefore likely to be used. INPUTS CardHandle - Same handle as that used when OwnCard() was called. buffer - Pointer to a buffer where the tuple will be copied. The buffer should be at least as large as "size" + 8 (see use of "size" argument below). Therefore the minimum buffer size is 8 bytes. See NOTES below. tuplecode - The tuple code you want to search for. This is a ULONG value. The upper 16 bits should be 0, or a number between 1-32K where a value of 0 means you want to find the first tuple match, a value of 1 the second, etc. For example - 0x41 means find the FIRST tuple equal to $41. ((1<<16)|(0x41)) means find the SECOND tuple equal to $41. ((2<<16)|(0x41)) means find the THIRD tuple equal to $41. size - The maximum number of bytes you want copied (not including the tuple code, and link). The actual number of bytes copied may be less than "size" if the tuple link field is less than "size". A size of 0 will result in only the tuple code, and link being copied to your buffer if the tuple is found. If you do not care how many bytes are copied, any unsigned value of 255 or greater will do. In this case a maximum of 257 bytes might be copied to your buffer (if the tuple link field is the maximum of 255). Other sizes are useful if you know the size of the tuple you want copied, or you know there are active registers stored within the tuple, and only want to copy a portion of a tuple. RETURNS TRUE if the tuple was found, and copied, else FALSE. This function may also return false if the CIS is believed to be corrupt, or if the card is removed while reading the tuples. NOTES This function can be called multiple times (adjusting the "size" argument) to read a tuple of variable length, or unknown size. Your supplied buffered is used by this function for working storage - the contents of it will be modified even if this function fails to find the tuple you want a copy of. This function should NOT be used to find/copy tuples of type : - CISTPL_LONGLINK_A - CISTPL_LONGLINK_C - CISTPL_NO_LINK - CISTPL_LINKTARGET - CISTPL_NULL - CISTPL_END These tuples are automatically handled for you by this function. SEE ALSO OwnCard()