Provided by: systemtap-doc_2.9-2ubuntu2_all 

NAME
function::gettimeofday_us - Number of microseconds since UNIX epoch
SYNOPSIS
gettimeofday_us:long()
ARGUMENTS
None
DESCRIPTION
This function returns the number of microseconds since the UNIX epoch.
SEE ALSO
tapset::timestamp_gtod(3stap)
SystemTap Tapset Reference April 2016 FUNCTION::GETTIMEOFD(3stap)