1Net::SSH::Perl::Comp(3)User Contributed Perl DocumentatioNnet::SSH::Perl::Comp(3)
2
3
4
6 Net::SSH::Perl::Comp - Compression/Decompression base class
7
9 use Net::SSH::Perl::Comp;
10 my $comp = Net::SSH::Perl::Comp->new( $comp_type );
11 $comp->compress($data);
12
14 Net::SSH::Perl::Comp is a base class for compression/decompression
15 classes. Currently the only such class is the Zlib implementation
16 (using Compress::Zlib), which is the class Net::SSH::Perl::Comp::Zlib.
17
18 Each compression object generally has its own internal "state"; this
19 state changes when you compress or decompress data. The SSH protocol
20 dictates that you must have two separate objects to compress and
21 decompress data: one for compression, one for decompression. So, for
22 example, you would create two Net::SSH::Perl::Comp objects:
23
24 my $in = Net::SSH::Perl::Comp->new('Zlib');
25 my $inflated = $in->decompress($data);
26
27 my $out = Net::SSH::Perl::Comp->new('Zlib');
28 my $deflated = $out->compress($data);
29
31 $comp = Net::SSH::Perl::Comp->new( $comp_type [, @args ] )
32 Constructs a new compression object of compression type $comp_type and
33 returns that object.
34
35 If @args are provided, the class's init method is called with those
36 arguments, for any post-creation initialization.
37
38 $comp->init($level)
39 Initializes $comp and sets the compression level to $level. This
40 method will be called automatically from new if you've provided @args
41 to new. So, for example, you could write:
42
43 my $comp = Net::SSH::Perl::Comp->new('Zlib', 5);
44
45 To create a new Zlib compression object and initialize its compression
46 level to 5.
47
48 $comp->compress( $data )
49 Compresses $data using the underlying compression mechanism; returns
50 the compressed data.
51
52 $comp->decompress( $data )
53 Decompresses $data using the underlying decompression mechanism;
54 returns the decompressed data.
55
56 $comp->enable
57 "Enables" the compression object. This is useful in the context of the
58 key exchange (Kex) classes, which create a new compression object
59 during key negotiation, but don't actually turn it on ("enable" it)
60 until receiving/sending the SSH2_MSG_NEWKEYS message.
61
62 Net::SSH::Perl::Comp objects (and subclasses) are disabled by default.
63
64 $comp->enabled
65 Returns the state of the "enabled" flag, ie. whether the compression
66 object is "turned on".
67
68 This is used by Net::SSH::Perl::Packet when determining whether data it
69 receives/sends to the server should be decompressed/compressed,
70 respectively.
71
73 Please see the Net::SSH::Perl manpage for author, copyright, and
74 license information.
75
76
77
78perl v5.32.0 2020-07-28 Net::SSH::Perl::Comp(3)