class IO::Hexdump
Overview
IO object that prints an hexadecimal dump of all transferred data.
Especially useful for debugging binary protocols on an IO, to understand better when and how data is sent or received.
By default IO::Hexdump
won't print anything; you must specify which of
#read
, #write
or both you want to print.
Example:
require "io/hexdump"
socket = IO::Memory.new("abc")
io = IO::Hexdump.new(socket, output: STDERR, read: true)
When data is read from io it will print something akin to the following on STDERR:
00000000 50 52 49 20 2a 20 48 54 54 50 2f 32 2e 30 0d 0a PRI * HTTP/2.0..
00000010 0d 0a 53 4d 0d 0a 0d 0a ..SM....
00000000 00 00 00 04 ....
00000000 00 .
00000000 00 00 00 00 ....
Defined in:
io/hexdump.crConstructors
Instance Method Summary
- #close(*args, **options)
- #close(*args, **options, &)
- #closed?(*args, **options)
- #closed?(*args, **options, &)
- #flush(*args, **options)
- #flush(*args, **options, &)
- #peek(*args, **options)
- #peek(*args, **options, &)
- #pos(*args, **options, &)
- #pos(*args, **options)
-
#pos=(arg)
Sets the current position (in bytes) in this
IO
. -
#read(buf : Bytes)
Reads at most slice.size bytes from this
IO
into slice. - #seek(*args, **options)
- #seek(*args, **options, &)
- #tty?(*args, **options, &)
- #tty?(*args, **options)
-
#write(buf : Bytes) : Nil
Writes the contents of slice into this
IO
.
Instance methods inherited from class IO
<<(obj) : self
<<,
close
close,
closed?
closed?,
each_byte(&) : Nileach_byte each_byte, each_char(&) : Nil
each_char each_char, each_line(*args, **options, &block : String -> ) : Nil
each_line(*args, **options) each_line, encoding : String encoding, flush flush, gets(delimiter : Char, limit : Int, chomp = false) : String?
gets(delimiter : Char, chomp = false) : String?
gets(chomp = true) : String?
gets(limit : Int, chomp = false) : String?
gets(delimiter : String, chomp = false) : String? gets, gets_to_end : String gets_to_end, peek : Bytes? peek, pos pos, pos=(value) pos=, print(*objects : _) : Nil
print(obj) : Nil print, printf(format_string, *args) : Nil
printf(format_string, args : Array | Tuple) : Nil printf, puts(*objects : _) : Nil
puts : Nil
puts(obj) : Nil
puts(string : String) : Nil puts, read(slice : Bytes) read, read_at(offset, bytesize, &) read_at, read_byte : UInt8? read_byte, read_bytes(type, format : IO::ByteFormat = IO::ByteFormat::SystemEndian) read_bytes, read_char : Char? read_char, read_fully(slice : Bytes) read_fully, read_fully?(slice : Bytes) read_fully?, read_line(*args, **options) : String read_line, read_string(bytesize : Int) : String read_string, read_utf8(slice : Bytes) read_utf8, read_utf8_byte read_utf8_byte, rewind rewind, seek(offset, whence : Seek = Seek::Set) seek, set_encoding(encoding : String, invalid : Symbol? = nil) set_encoding, skip(bytes_count : Int) : Nil skip, skip_to_end : Nil skip_to_end, tell tell, tty? : Bool tty?, write(slice : Bytes) : Nil write, write_byte(byte : UInt8) write_byte, write_bytes(object, format : IO::ByteFormat = IO::ByteFormat::SystemEndian) write_bytes, write_utf8(slice : Bytes) write_utf8
Class methods inherited from class IO
copy(src, dst, limit : Int) : Int64copy(src, dst) : Int64 copy, pipe(read_blocking = false, write_blocking = false) : Tuple(IO::FileDescriptor, IO::FileDescriptor)
pipe(read_blocking = false, write_blocking = false, &) pipe, same_content?(stream1 : IO, stream2 : IO) same_content?
Instance methods inherited from class Reference
==(other : self)==(other : JSON::Any)
==(other : YAML::Any)
==(other) ==, dup dup, hash(hasher) hash, inspect(io : IO) : Nil inspect, object_id : UInt64 object_id, pretty_print(pp) : Nil pretty_print, same?(other : Reference)
same?(other : Nil) same?, to_s(io : IO) : Nil to_s
Constructor methods inherited from class Reference
new
new
Instance methods inherited from class Object
! : Bool
!,
!=(other)
!=,
!~(other)
!~,
==(other)
==,
===(other : JSON::Any)===(other : YAML::Any)
===(other) ===, =~(other) =~, as(type : Class) as, as?(type : Class) as?, class class, dup dup, hash(hasher)
hash hash, in?(*values : Object) : Bool
in?(collection) : Bool in?, inspect : String
inspect(io : IO) : Nil inspect, is_a?(type : Class) : Bool is_a?, itself itself, nil? : Bool nil?, not_nil! not_nil!, pretty_inspect(width = 79, newline = "\n", indent = 0) : String pretty_inspect, pretty_print(pp : PrettyPrint) : Nil pretty_print, responds_to?(name : Symbol) : Bool responds_to?, tap(&) tap, to_json(io : IO)
to_json to_json, to_pretty_json(io : IO, indent : String = " ")
to_pretty_json(indent : String = " ") to_pretty_json, to_s : String
to_s(io : IO) : Nil to_s, to_yaml(io : IO)
to_yaml to_yaml, try(&) try, unsafe_as(type : T.class) forall T unsafe_as
Class methods inherited from class Object
from_json(string_or_io, root : String)from_json(string_or_io) from_json, from_yaml(string_or_io : String | IO) from_yaml
Constructor Detail
Instance Method Detail
Sets the current position (in bytes) in this IO
.
The IO
class raises on this method, but some subclasses, notable
IO::FileDescriptor
and IO::Memory
implement it.
File.write("testfile", "hello")
file = File.new("testfile")
file.pos = 3
file.gets_to_end # => "lo"
Reads at most slice.size bytes from this IO
into slice.
Returns the number of bytes read, which is 0 if and only if there is no
more data to read (so checking for 0 is the way to detect end of file).
io = IO::Memory.new "hello"
slice = Bytes.new(4)
io.read(slice) # => 4
slice # => Bytes[104, 101, 108, 108]
io.read(slice) # => 1
slice # => Bytes[111, 101, 108, 108]
io.read(slice) # => 0