NAME

       dtrace - Dtrace compatible user application static probe generation tool.

SYNOPSIS

       dtrace -s file [OPTIONS]

DESCRIPTION

       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.

OPTIONS

       -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.

EXAMPLES

       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  definition  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

       Semaphores are flag variables used by probes as a way of bypassing potentially costly processing to  pre‐
       pare  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  sema‐
       phore  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.

SEE ALSO

       stap(1),
       stappaths(7)

BUGS

       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

                                                                                                       DTRACE(1)