z_stream zstream1, zstream2;
zstream1.zalloc = Z_NULL;
zstream1.zfree = Z_NULL;
zstream1.opaque = Z_NULL;
zstream2.zalloc = Z_NULL;
zstream2.zfree = Z_NULL;
zstream2.opaque = Z_NULL;

if (deflateInit(&zstream1, Z_DEFAULT_COMPRESSION) !=     Z_OK || deflateInit(&zstream2, Z_DEFAULT_COMPRESSION) != Z_OK) {
        return 1;
    }