bionic (3) ns_zlib.3aolserver.gz

NAME

       ns_zlib - Zlib compression support

SYNOPSIS

       ns_zlib compress string
       ns_zlib gunzip file
       ns_zlib gzip string
       ns_zlib gzipfile file
       ns_zlib uncompress string
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DESCRIPTION

       The  ns_zlib command enables compressing and uncompressing of strings or files.  The command is available
       if the nszlib.so module is loaded into AOLserver or  the  libnszlib.so,  nszlib.dll,  or  libnszlib.dylib
       dynamic library is loaded using the load command in a suitable tclsh such as nstclsh.

       ns_zlib compress string
              This  command  compresses the given string and returns a Tcl byte array object with the compressed
              data.

       ns_zlib gunzip file
              This command uncompresses the contents of the given gzipped file  and  returns  a  string  as  the
              result.

       ns_zlib gzipfile file
              This  command  is  similar  to the gzip shell routines, compressing the given file into a new file
              with the .gz extension.  If successful, the original uncompressed file is deleted.

       ns_zlib uncompress bytearray
              This command takes a byte array object which includes compressed data and returns an  uncompressed
              string object.

EXAMPLES

       The following examples demonstrate compressing and uncompressing a string;

              # Compress Tcl string
              set test "This is test string"
              set data [ns_zlib compress $test]
              set test [ns_zlib uncompress $data]
              --> returns "This is test string"

              # Compress the string into gzip format
              set gzip [ns_zlib gzip $test]

              # Save as gzip file
              set fd [open /tmp/test.gz w]
              fconfigure $fd -translation binary -encoding binary
              puts -nonewline $fd $gzip
              close $fd

              # Uncompress gzipped file
              set test [ns_zlib gunzip /tmp/test.gz]
              --> returns "This is test string"

SEE ALSO

       ns_adp_ctl(n), load(n)

KEYWORDS

       GZIP, compress, uncompress