Beefy Boxes and Bandwidth Generously Provided by pair Networks
Come for the quick hacks, stay for the epiphanies.
 
PerlMonks  

comment on

( [id://3333]=superdoc: print w/replies, xml ) Need Help??
I would continue to write data on my TCP socket until the send window will be 0 and eventually I may lose the data.

That is not how TCP works: once the TCP sending buffer becomes full, the kernel would block any write operation until data is transmitted to the other side leaving some buffer space free again. No data is lost.

If you don't want to block, you would have to use select or some of the modules wrapping it (or similar syscalls). For complex cases, using an event-driven programing framework such as AnyEvent, POE, Mojo::IOLoop, IO::Async, etc. may help too.

Update: I forget to say that no data is lost in TCP operations, but you have to check the result of syswrite which is the number of bytes written. It is not guaranteed that syswrite would write all the data passed, so you will have to call it repeatly, adjusting the offset until all the data is sent (well, actually, buffered by the kernel!).


In reply to Re: function to count pending packets in TCP socket by salva
in thread function to count pending packets in TCP socket by Anonymous Monk

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post; it's "PerlMonks-approved HTML":



  • Are you posting in the right place? Check out Where do I post X? to know for sure.
  • Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
    <code> <a> <b> <big> <blockquote> <br /> <dd> <dl> <dt> <em> <font> <h1> <h2> <h3> <h4> <h5> <h6> <hr /> <i> <li> <nbsp> <ol> <p> <small> <strike> <strong> <sub> <sup> <table> <td> <th> <tr> <tt> <u> <ul>
  • Snippets of code should be wrapped in <code> tags not <pre> tags. In fact, <pre> tags should generally be avoided. If they must be used, extreme care should be taken to ensure that their contents do not have long lines (<70 chars), in order to prevent horizontal scrolling (and possible janitor intervention).
  • Want more info? How to link or How to display code and escape characters are good places to start.
Log In?
Username:
Password:

What's my password?
Create A New User
Domain Nodelet?
Chatterbox?
and the web crawler heard nothing...

How do I use this?Last hourOther CB clients
Other Users?
Others meditating upon the Monastery: (3)
As of 2024-03-29 07:31 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    No recent polls found