you can print out more than one header the following way:

print "Content-Type: text/html\n";
print "Set-Cookie: $cookie_object\n\n";
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notice you can print individual headers out by ending them with a simple \n the last header must have \n\n to finish prionting all the headers. depending on whethere you are using strict or warnings printing out multiple:

print "Content-Type: text/html\n\n";
print "Content-Type: text/html\n\n";
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will produce some warnings. Printing out a header informs the program of the type of data being processed