Provided by: systemtap-doc_2.3-1ubuntu1.4_all 

NAME
function::error - Send an error message
SYNOPSIS
error(msg:string)
ARGUMENTS
msg
The formatted message string
DESCRIPTION
An implicit end-of-line is added. staprun prepends the string “ERROR:”. Sending an error message aborts
the currently running probe. Depending on the MAXERRORS parameter, it may trigger an exit.
SystemTap Tapset Reference March 2016 FUNCTION::ERROR(3stap)