Commit 2a0c7ea4 authored by Daniel Stenberg's avatar Daniel Stenberg
Browse files

curl_easy_setopt.3: mention TFTP read callback flaw 

The read callback must return the exact requested amount of data when it
is used for doing TFTP uploads. This is due to how it deals with data
internally. This could/should be fixed but for now we document the
existing behavior.

Reported by: Colin Blair
Bug: http://curl.haxx.se/mail/lib-2011-03/0319.html
parent 4913a08c

docs/libcurl/curl_easy_setopt.3

+4 −0
Original line number Diff line number Diff line
@@ -208,6 +208,10 @@ From 7.18.0, the function can return CURL_READFUNC_PAUSE which then will cause 
reading from this connection to become paused. See \fIcurl_easy_pause(3)\fP

for further details.



\fBBugs\fP: when doing TFTP uploads, you must return the exact amount of data

that the callback wants, or it will be considered the final packet by the

server end and the transfer will end there.



If you set this callback pointer to NULL, or don't set it at all, the default

internal read function will be used. It is doing an fread() on the FILE *

userdata set with \fICURLOPT_READDATA\fP.