Let’s define serialization first, then we can talk about why it’s so useful. Serialization is simply turning an existing object into a byte array. This byte array represents the class of the object, the version of the object, and the internal state of the object. This byte array can then be used between JVM’s running … Read more
The word “stream” has been chosen because it represents (in real life) a very similar meaning to what we want to convey when we use it. Let’s forget about the backing store for a little, and start thinking about the analogy to a water stream. You receive a continuous flow of data, just like water … Read more
The compiler can evaluate the function printcbase() as this: void printcbase(cbase* b ){ int a = b->FooA(); // line 1 int b = b->FooB(); // line 2 std::cout << a; // line 3 std::cout << b; // line 4 stc::cout << std::endl; } or some of many permutatins of lines marked as 1 – 4. … Read more
The expressionstd::ostringstream() creates a temporary, and operator<< which takes const char* as argument is a free function, but this free function cannot be called on a temporary, as the type of the first parameter of the function is std::ostream& which cannot be bound to temporary object. Having said that, <<std::ostringstream() << “some data” resolves to … Read more
I’m not sure about what you’re trying to achieve. You can read stdin with the URL php://stdin. But that’s the stdin from the PHP command line, not the one from pdftk (through exec). But I’ll give a +1 for proc_open() <?php $cmd = sprintf(‘pdftk %s fill_form %s output -‘,’blank_form.pdf’, raw2xfdf($_POST)); $descriptorspec = array( 0 => … Read more
There’s a really ugly way to capture stderr and stdout in two separate variables without temporary files (if you like plumbing), using process substitution, source, and declare appropriately. I’ll call your command banana. You can mimic such a command with a function: banana() { echo “banana to stdout” echo >&2 “banana to stderr” } I’ll … Read more
open-uri is part of the standard Ruby library, and it will redefine the behavior of open so that you can open a url, as well as a local file. It returns a File object, so you should be able to call methods like read and readlines. require ‘open-uri’ file_contents = open(‘local-file.txt’) { |f| f.read } … Read more
The reason you are not allowed to copy a stream is that it doesn’t make sense to copy a stream. If you explain what it is that you are trying to do, there’s certainly a way to do it. If you want a chunk of data you can copy, use a string. But a stream … Read more
The key word is unexpected. If you use DataInputStream and read a 4 byte integer but there were only 3 bytes remaining in the stream you’ll get an EOFException. But if you call read() at the end of stream you’ll just get -1 back and no exception.
You probably want something like this. Either checking the length fails, or the BinaryReader is doing seeks behind the scenes. HttpWebRequest myReq = (HttpWebRequest)WebRequest.Create(url); WebResponse myResp = myReq.GetResponse(); byte[] b = null; using( Stream stream = myResp.GetResponseStream() ) using( MemoryStream ms = new MemoryStream() ) { int count = 0; do { byte[] buf = … Read more