Description
string 
gzcompress ( string data [, int level] )
   This function compress the given string using the ZLIB
   data format.
  
   For details on the ZLIB compression algorithm see the document
   "ZLIB Compressed Data Format
   Specification version 3.3" (RFC 1950).
  
Note: 
    This is not the same as gzip compression,
    which includes some header data. See gzencode()
    for gzip compression.