Zlib:crc32 combine

uLong crc32_combine(uLong crc1, uLong crc2,z_off_t len2);

Combine two CRC-32 check values into one. For two sequences of bytes, seq1 and seq2 with lengths len1 and len2, CRC-32 check values were calculated for each, crc1 and crc2. () returns the CRC-32 check value of seq1 and seq2 concatenated, requiring only crc1, crc2, and len2.

Pseudocode definition:

crc1:=crc32(0L,seq1,len1);



crc2:=crc32(0L,seq2,len2);



crc32_combine(crc1,crc2,len2):=crc32(crc1,seq2,len2);