actually - annoyingly - my previous solution didn't help. SAS still applies a 'wrapper' to the HTML, destroying any header information (eg Javascript functions).
The following will fix it - basically run a dummy piece of code to create the reference in your EG session, then proceed to overwrite it with some pure html of your choosing! The link will remain...
%let libWORK=%sysfunc(pathname(WORK)); * work lib is on UNIX ;
ods html body="&libWORK./MYFILE.htm" ;
data _null_;
file print;
put "this will be overwritten! ";
run;
ods html close;
data _null_;
file "&libWORK./MYFILE.htm";
put '<html>' /
' <head>'/
' <title> A Title </title>'/
'</head> <body> some content </body> </html>';
run;