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NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLES | SEMAPHORES | SEE ALSO | BUGS | COLOPHON |
DTRACE(1) General Commands Manual DTRACE(1)
dtrace - Dtrace compatible user application static probe generation
tool.
dtrace -s file [OPTIONS]
The dtrace command converts probe descriptions defined in file.d into
a probe header file via the -h option or a probe description file via
the -G option.
-h generate a systemtap header file.
-G generate a systemtap probe definition object file.
-o file
is the name of the output file. If the -G option is given
then the output file will be called file.o; if the -h option
is given then the output file will be called file.h.
-C run the cpp preprocessor on the input file when the -h option
is given.
-I file
give this include path to cpp when the -C option is given.
-k keep temporary files, for example the C language source for
the -G option.
Systemtap is source compatible with dtrace user application static
probe support. Given a file test.d containing:
provider sdt_probes
{
probe test_0 (int type);
probe test_1 (struct astruct node);
};
struct astruct {int a; int b;};
Then the command "dtrace -s test.d -G" will create the probe defini‐
tion file test.o and the command "dtrace -stest.d -h" will create the
probe header file test.h Subsequently the application can use the
generated macros this way:
#include "test.h"
...
struct astruct s;
...
SDT_PROBES_TEST_0(value);
...
if (SDT_PROBES_TEST_1_ENABLED())
SDT_PROBES_TEST_1(expensive_function(s));
Semaphores are flag variables used by probes as a way of bypassing
potentially costly processing to prepare arguments for probes that
may not even be active. They are automatically set/cleared by
systemtap when a relevant script is running, so the argument setup
cost is only paid when necessary. These semaphore variables are
defined within the the "test.o" object file, which must therefore be
linked into an application.
Sometimes, semaphore variables are not necessary nor helpful.
Skipping them can simplify the build process, by omitting the extra
"test.o" file. To skip dependence upon semaphore variables, include
"<sys/sdt.h>" within the application before "test.h":
#include <sys/sdt.h>
#include "test.h"
...
struct astruct s;
...
SDT_PROBES_TEST_0(value);
...
if (SDT_PROBES_TEST_1_ENABLED())
SDT_PROBES_TEST_1(cheap_function(s));
In this mode, the ENABLED() test is fixed at 1.
stap(1),
stappaths(7)
Use the Bugzilla link of the project web page or our mailing list.
http://sourceware.org/systemtap/ , <systemtap@sourceware.org>.
error::reporting(7stap),
https://sourceware.org/systemtap/wiki/HowToReportBugs
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
DTRACE(1)