Question

I wonder why I can’t YAML load right after YAML dump

I tried following code, but there is no “end” printing on console

could someone tell me what’s wrong with me?

thanking you

server side ruby code

require 'socket'
require 'yaml'
h = []
s = TCPServer.open('localhost',2200)
c = s.accept
loop do
    YAML.dump(h,c)
    YAML.load(c)
    puts "end"
end

client side ruby code

require 'socket'
require 'yaml'
d = []
s = TCPSocket.open('localhost',2200)
loop do
    d = YAML.load(s)
    YAML.dump("client",s)
    puts "end"
end

Answer 1

YAML doesn’t know in advance how many bytes to read, so it tries to read as much as possible and waits forever. There is no end_of_record for TCP/IP.

require 'socket'
require 'yaml'
h = []
s = TCPServer.open('localhost',2200)
c = s.accept
loop do
    s = YAML.dump(h)
    c.write([s.length].pack("I"))
    c.write(s)
    length = c.read(4).unpack("I")[0]
    p YAML.load(c.read(length))
end



require 'socket'
require 'yaml'
d = []
c = TCPSocket.open('localhost',2200)
loop do
    length = c.read(4).unpack("I")[0]
    p YAML.load(c.read(length))
    s = YAML.dump("client")
    c.write([s.length].pack("I"))
    c.write(s)
end