if {![exists -proc require]} {
	proc require {args} {{done {}}} {
		foreach file $args {
			if {$file ni $done} {
				uplevel source "/mod/webif/lib/$file"
				lappend $done $file
			}
		}
	}

	proc httpheader {{type "text/html"} {cache 0} {extra ""}} {{done 0}} {
		if {$done} return
		if {!$cache} {
			puts -nonewline "Content-Type: $type; charset=\"UTF-8\"; no-cache\r\n"
			puts -nonewline "Expires: -1\r\n"
			puts -nonewline "Pragma: no-cache\r\n"
			puts -nonewline "Cache-Control: no-cache\r\n"
		} else {
			puts "Content-Type: $type; charset=\"UTF-8\"\r\n"
		}
		puts -nonewline $extra
		puts -nonewline "\r\n"
		set done 1
	}

	proc header {{type "text/html"} {cache 0}} {
		httpheader $type $cache
		uplevel source /mod/webif/html/lib/header.jim
	}

	proc footer {} {
		uplevel source /mod/webif/html/lib/footer.jim
	}

	proc mheader {} {
		uplevel source /mod/webif/html/m/lib/header.jim
	}

	proc mfooter {} {
		uplevel source /mod/webif/html/m/lib/footer.jim
	}

	require fileops
}