NAME | SYNOPSIS | DESCRIPTION | OPTIONS | ARGUMENTS | EXAMPLES | SAFETY AND SECURITY | SEE ALSO | BUGS | COLOPHON |
STAPDYN(8) System Manager's Manual STAPDYN(8)
stapdyn - systemtap dyninst runtime
stapdyn [ OPTIONS ] MODULE [ MODULE-OPTIONS ]
The stapdyn program is the dyninst back-end of the Systemtap tool. It expects a shared library produced by the front-end stap tool, when run with --dyninst. Splitting the systemtap tool into a front-end and a back-end allows a user to compile a systemtap script on a development machine that has the debugging information (need to compile the script) and then transfer the resulting shared object to a production machine that doesn't have any development tools or debugging information installed. Please refer to stappaths (7) for the version number, or run rpm -q systemtap (fedora/red hat) apt-get -v systemtap (ubuntu)
The stapdyn program supports the following options. Any other option prints a list of supported options. -v Verbose mode. -V Print version number and exit. -w Suppress warnings from the script. -c CMD Command CMD will be run and the stapdyn program will exit when CMD does. The '_stp_target' variable will contain the pid for CMD. -x PID The '_stp_target' variable will be set to PID. -o FILE Send output to FILE. If the module uses bulk mode, the output will be in percpu files FILE_x(FILE_cpux in background and bulk mode) where 'x' is the cpu number. This supports strftime(3) formats for FILE. -C WHEN Control coloring of error messages. WHEN must be either "never", "always", or "auto" (i.e. enable only if at a termi‐ nal). If the option is missing, then "auto" is assumed. Colors can be modified using the SYSTEMTAP_COLORS environment vari‐ able. See the stap(1) manual page for more information on syn‐ tax and behaviour. var1=val Sets the value of global variable var1 to val. Global vari‐ ables contained within a script are treated as options and can be set from the stapdyn command line.
MODULE is either a module path or a module name. If it is a module name, the module will be looked for in the following directory (where 'VERSION' is the output of "uname -r"): /lib/modules/VERSION/systemtap $ stap --dyninst -p4 -m mod1 -e 'global var1="foo"; probe begin{printf("%s\n", var1); exit()}' Running this with an additional module argument: $ stapdyn mod1.so var1="HelloWorld" HelloWorld Spaces and exclamation marks currently cannot be passed into global variables this way.
See the stapex(3stap) manual page for a collection of sample scripts. Here is a very basic example of how to use stapdyn. First, use stap to compile a script. The stap program will report the pathname to the resulting module. $ stap --dyninst -p4 -e 'probe begin { printf("Hello World!\n"); exit() }' /home/user/.systemtap/cache/85/stap_8553d83f78c_265.so Run stapdyn with the pathname to the module as an argument. $ stapdyn /home/user/.systemtap/cache/85/stap_8553d83f78c_265.so Hello World!
Systemtap, in DynInst mode, is a developer tool, and runs completely unprivileged. The Linux kernel will only permit one's own processes to be accessed, which is enforced by the ptrace(2) system call. See the stap(1) manual page for additional information on safety and security.
stap(1), stapprobes(3stap), stap-server(8), staprun(8), stapex(3stap)
Use the Bugzilla link of the project web page or our mailing list. http://sourceware.org/systemtap/ , <systemtap@sourceware.org>.
This page is part of the systemtap (a tracing and live-system
analysis tool) project. Information about the project can be found
at ⟨https://sourceware.org/systemtap/⟩. If you have a bug report for
this manual page, send it to systemtap@sourceware.org. This page was
obtained from the project's upstream Git repository
⟨git://sourceware.org/git/systemtap.git⟩ on 2017-07-05. If you dis‐
cover any rendering problems in this HTML version of the page, or you
believe there is a better or more up-to-date source for the page, or
you have corrections or improvements to the information in this
COLOPHON (which is not part of the original manual page), send a mail
to man-pages@man7.org
STAPDYN(8)
Pages that refer to this page: stap(1), staprun(8)