curl.1: explain the SMTP data expected for -T

Fixes #1107

Reported-by: Adam Piggott

diff --git a/docs/curl.1 b/docs/curl.1
index f5375ed7f1e1de259324c2334b8b5aa63e15504c..9e96d0c98eb20da6b7a3561a22ee644f3d9f81e3 100644 (file)
--- a/docs/curl.1
+++ b/docs/curl.1
@@ -1774,6 +1774,11 @@ curl -T "{file1,file2}" http://www.example.com
 or even
 
 curl -T "img[1-1000].png" ftp://ftp.example.com/upload/
+
+When uploading to an SMTP server: the uploaded data is assumed to be RFC 5322
+formatted. It has to feature the necessary set of headers and mail body
+formatted correctly by the user as curl will not transcode nor encode it
+further in any way.
 .IP "--tcp-nodelay"
 Turn on the TCP_NODELAY option. See the \fIcurl_easy_setopt(3)\fP man page for
 details about this option. (Added in 7.11.2)