@param dst output buffer (must have size >= BGZF_MAX_BLOCK_SIZE)
@param dlen size of output buffer; updated on return to the number
of bytes actually written to dst
@param src buffer to be compressed
@param slen size of data to compress (must be <= BGZF_BLOCK_SIZE)
@param level compression level
@return 0 on success and negative on error
Compress a single BGZF block.
@param dst output buffer (must have size >= BGZF_MAX_BLOCK_SIZE) @param dlen size of output buffer; updated on return to the number of bytes actually written to dst @param src buffer to be compressed @param slen size of data to compress (must be <= BGZF_BLOCK_SIZE) @param level compression level @return 0 on success and negative on error