Provided by: systemtap-doc_3.1-3ubuntu0.1_all 

NAME
function::long_arg - Return function argument as signed long
SYNOPSIS
long_arg:long(n:long)
ARGUMENTS
n
index of argument to return
DESCRIPTION
Return the value of argument n as a signed long. On architectures where a long is 32 bits, the value is
sign-extended to 64 bits.
SEE ALSO
tapset::registers(3stap)
SystemTap Tapset Reference March 2016 FUNCTION::LONG_ARG(3stap)