Hello dear Monks,

I tried reading from a socket as one might from a file (I know, no error handling, that's not the point here): 

my $buf;
my $read;
while(($read = $s->read( $buf, 1024 )) > 0) {
    my $chunk = substr $buf, $read;
    # process chunk
}

[download]
When the socket is not closed after the sender sent its stuff the read blocks until 1024 bytes are available. So if I don't know in advance how many data I'm about to receive, I have to use a buffer size of one. Is this correct? If yes, isn't this inefficient? If not, how would a better solution look like?

An example would be parsing an HTTP header. The length field is not always at the same position so until I find it, I have to take small steps in order not to try to read more bytes than are available in the current response. With keep-alive that socket stays open so no EOF there.

The main reason I ask is because I do a lot of Java programming. When you read from a socket in Java the read returns even if not enough data is received to fill the whole buffer in a short amount of time.

In reply to read from socket blocks until buffer is full by Anonymous Monk

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