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POHow can I send [SYN] with bare sockets?
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copied!<p>I'm writing a bare bone ftp client just using sockets on <strong>VxWorks</strong> and I now would like to receive directory contents. For that I need to send a <code>Request: LIST</code> and following a <code>[SYN]</code> which initiates the data transfer back to me but I'm wondering how I do this with simple sockets? My code to send the <code>LIST</code> just looks like this:</p> <pre><code>char lst[6] = "LIST"; lst[4] = 0x0d; // add empty characters on back lst[5] = 0x0a; if (write (sFd, (char *) &lst, 6) == ERROR) { perror ("write"); close (sFd); return ERROR; } if (read (sFd, replyBuf, REPLY_MSG_SIZE) < 0) { perror ("read"); close (sFd); return ERROR; } printf ("MESSAGE FROM SERVER:\n%s\n", replyBuf); </code></pre> <p>but it actually gets stuck in the read() until it times out as the server doesn't respond unless i send a 'SYNC` to initiate the connection.</p> <p><strong>edit</strong> </p> <p>Upon suggestion, I replaced the addtion of 0x0d and 0x0a at the end of my string with <strong>\r\n</strong> directly top the string which changed my code to:</p> <pre><code>char lst[6] = "LIST\r\n"; if (write (sFd, (char *) &lst, strlen(lst)) == ERROR) { perror ("write"); close (sFd); return ERROR; } if (read (sFd, replyBuf, REPLY_MSG_SIZE) < 0) { perror ("read"); close (sFd); return ERROR; } printf ("MESSAGE FROM SERVER:\n%s\n", replyBuf); </code></pre> <p>but I get exactly the same result, my client does not send a <code>SYNC</code> message - why not I am wondering...?</p>

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