Red Hat ENTERPRISE LINUX 5.4 - SYSTEMTAP BEGINNERS GUIDE Manual page 22

Chapter 3. Understanding How SystemTap Works
probe syscall.open
{
printf ("%s(%d) open\n", execname(), pid())
}
Example 3.5. variables-in-printf-statements.stp
Example 3.5, "variables-in-printf-statements.stp"
call open; for each event, it prints the current execname() (a string with the executable name) and
pid() (the current process ID number), followed by the word open. A snippet of this probe's output
would look like:
vmware-guestd(2206) open
hald(2360) open
hald(2360) open
hald(2360) open
df(3433) open
df(3433) open
df(3433) open
hald(2360) open
SystemTap Functions
SystemTap supports a wide variety of functions that can be used as printf () arguments.
Example 3.5, "variables-in-printf-statements.stp"
of the process that called a kernel function/performed a system call) and pid() (current process ID).
The following is a list of commonly-used SystemTap functions:
tid()
The ID of the current thread.
uid()
The ID of the current user.
cpu()
The current CPU number.
gettimeofday_s()
The number of seconds since UNIX epoch (January 1, 1970).
ctime()
Convert number of seconds since UNIX epoch to date.
pp()
A string describing the probe point currently being handled.
thread_indent()
This particular function is quite useful, providing you with a way to better organize your print
results. The function takes one argument, an indentation delta, which indicates how many spaces
to add or remove from a thread's "indentation counter". It then returns a string with some generic
trace data along with an appropriate number of indentation spaces.
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instructs SystemTap to probe all entries to the system
uses the SystemTap functions execname() (name