antirice provides a valuable observation. The underlying issue is this: read() buffers; sysread() doesn't. This matters when the socket is still open, as it will be when you use the   Connection: Keep-Alive header. This tells the web server that you expect to reuse the socket for additional requests. The web server obliges by keeping the socket open and by sending a Content-Length header in the response to tell you exactly how many bytes it is safe for you to read. If you try to read more, you'll block.

read(), given a buffer size to read, will wait for the socket to fill up the buffer, and will block until more bytes are available. sysread() will return the number of bytes that are actually available.

Alternatively, you could use the Content-Length that the web server has returned to you (and which you've squirreled away in $length), and read() only that many bytes.

In reply to Re: read aka fread(3) broken, sysread aka read(2) works IIS socket by dws
in thread read aka fread(3) broken, sysread aka read(2) works IIS socket by tachyon

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