Hai cercato la traduzione di typically da Coreano a Inglese

if a fourth string argument is passed, this string is inserted at the end of the header. this is typically used to add extra headers. multiple extra headers are separated with a newline.
you may need to add the user that your web server runs as to your sendmail configuration to prevent a 'x-warning' header from being added to the message when you set the envelope sender using this method.

additional_headers is inserted at the end of the header. this is typically used to add extra headers. multiple extra headers are separated with a newline ("\n").
additional_parameter additional_parameter is a mta command line parameter.

also, both ie and lynx ignore any nuls (\0) in the html stream, netscape does not. the best way to check for this is to compile the command line version of php (also known as the cgi version) and run your script from the command line. in *nix, pipe it through od -c and look for any \0 characters. if you are on windows you need to find an editor or some other program that lets you look at binary files. when netscape sees a nul in a file it will typically not output anything else on that line whereas both ie and lynx will.
the best way to check for this is to compile the command line the best way to check for this is to compile the command line version of php (also known as the cgi version) and run your script from the command line.