OK, I'm real confused now. I notice that my form has, in fact, stopped working. to clarify: I only noticed that there were underscores -- I didn't notice that the colons were still there and that, in fact, the program didn't work}. My guess is that the server doesn't like the colons.. :o) {As for the X-, not my choice: I simply scrape the form I get and try to return the right fields}. I didn't understand what you told me about the content/headers stuff. Here is {part of the} actual form I fetched 
<FORM action="...members/add" method="POST" enctype="multipart/form-da
+ta">
<input type="hidden" name="csrf_token" value="280200000069c97e705b7347
+000000746573746c6973742d66616e746173796661726d2e636f6d2b61646d696e3a3
+763663438346436393036323038363738613566383231623461323132353762356361
+3763633665">
[...]
<INPUT name="send_notifications_to_list_owner" type="RADIO" value="0" 
+>
 <INPUT name="send_notifications_to_list_owner" type="RADIO" value="1"
+ CHECKED >
  <TEXTAREA NAME=subscribees ROWS=10 COLS=70%></TEXTAREA>
[...]
<INPUT name="setmemberopts_btn" type="SUBMIT" value="Submit Your Chang
+es" >

[download]
Then what I do is set up a @fields array with 
@fields= (    ":csrf_token" => $csrf_token
                    subscribees => "$name <$email>",
               ":setmemberopts_btn" => 'Submit Your Changes',
               ":send_notifications_to_list_owner" => "1",
               );
$res = $ua->request(POST $_[0], \@fields);

[download]
and that not only doesn't work, but gets me an ugly 
<h3><strong><font color="red" size="+2">Error: </font></strong><em>The
+ form lifetime has expired. (request forgery check)</em></h3><center>
+<h2>Testlist mailing list administration<br>Membership&nbsp;Managemen
+t... Section</h2></center><hr>

[download]
I'm not sure what they check for the 'lifetime' but I bet it is the csrf_token. and I see in the request that every field name now has a colon in front of it {except for the fields that showed up in the request-content; they all have %3's in front of them}. So I feel trapped; is there a way to pass the underscores through to the server, but without the colons?? {short of my going into HTTP::Headers and actually tweaking the code to never "canonicalize"}

2018-08-13 Athanasius fixed code tag placement

In reply to Re^4: POST fieldnames with underscores by BernieC
in thread POST fieldnames with underscores by BernieC

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