curlmultiperform(3)           libcurl Manual           curlmultiperform(3)



NAME
       curlmultiperform - reads/writes available data from each easy handle

SYNOPSIS
       #include 

       CURLMcode  curlmultiperform(CURLM  *multihandle,  int  *runninghan-
       dles);

DESCRIPTION
       When the app thinks there's data available  for  the  multihandle,  it
       should  call  this  function to read/write whatever there is to read or
       write  right  now.  curlmultiperform()  returns  as   soon   as   the
       reads/writes  are done. This function does not require that there actu-
       ally is any data available for reading or that data can be written,  it
       can  be  called  just in case. It will write the number of handles that
       still transfer data in the second argument's integer-pointer.

       When you call curlmultiperform() and the amount of runninghandles is
       changed from the previous call (or is less than the amount of easy han-
       dles you've added to the multi handle), you know that there is  one  or
       more     transfers     less    "running".    You    can    then    call
       curlmultiinforead(3) to get information about each  individual  com-
       pleted transfer, and that returned info includes CURLcode and more.

RETURN VALUE
       CURLMcode type, general libcurl multi interface error code.

       If  you receive CURLMCALMULTIPERFORM, this basically means that you
       should call curlmultiperform  again,  before  you  select()  on  more
       actions. You don't have to do it immediately, but the return code means
       that libcurl may have more data available to return or that  there  may
       be more data to send off before it is "satisfied".

       NOTE that this only returns errors etc regarding the whole multi stack.
       There might still have occurred problems on individual  transfers  even
       when this function returns OK.

TYPICAL USAGE
       Most application will use curlmultifdset(3) to get the multihandle's
       file descriptors, then it'll wait for action on them using select() and
       as  soon  as  one or more of them are ready, curlmultiperform(3) gets
       called.

SEE ALSO
       curlmulticleanup(3),     curlmultiinit(3),     curlmultifdset(3),
       curlmultiinforead(3)



libcurl 7.9.5                    1 March 2002            curlmultiperform(3)