Description:
------------
ftp_put() in some cases returns FALSE after transfer of a file.
The last logged error in $php_errormsg is 
  "ftp_put() [function.ftp-put.php]: PORT command successful"

It is unclear if this is a problem within PHP:FTP, a clientside filesystem problem or a serverside problem.

The same script runs 100 transfers every 15 mins from one server off to different platforms of different flavours. We have recently encountered a HUGE increase of these errors which would indicate a problem in the source system.

As far as we can see, there is no (documented?) way to debug this problems and look into the server responses. There was one proposal how to solve something like this in
  https://bugs.php.net/bug.php?id=44059
but that never made it into the tree.






Test script:
---------------

$ftp         = ftp_connect($ftphost,21,15);
$ftp_login   = ftp_login($ftp, $ftpuser, $ftppass);
$ftp_pasv    = ftp_pasv($ftp, true);

$ftp_up      = ftp_put($ftp, $trgfile, $srcfile, FTP_BINARY); 

# now check upload status:
if (!$ftp_up) { 
  print "upload check failed [" . $php_errormsg . "]<";
} else {
  print "upload successful";
}




Expected result:
----------------
Access to some sort of log of last server messages.



Note: 
The last erromessage in php_errormsg is might be misleading.

Note 2:
Unless you're transferring to a server to which you have ftp-logfile access, it's impossible to debug this from the serverside.



Actual result:
--------------
ftp_put() returns FALSE for undebuggable reason.

Misleading or unclear messages in $php_errormsg