.h.hn[x;y;z]

Where

• x is the status code (string)
• y is the content type (symbol)
• z is the content (string)

returns as a string an HTTP error response.

q).h.hn["404";`txt;"Not found: favicon.ico"]
"HTTP/1.1 404\r\nContent-Type: text/plain\r\nConnection: close\r\nContent-Len..