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Diff for /wikisrc/tutorials/how_to_enable_and_run_dtrace.mdwn between versions 1.26 and 1.29

version 1.26, 2018/07/22 17:18:06 version 1.29, 2020/03/30 15:45:00
Line 101  Run the hello world script:  Line 101  Run the hello world script: 
     dtrace: script './hello.d' matched 1 probe      dtrace: script './hello.d' matched 1 probe
     CPU     ID                    FUNCTION:NAME      CPU     ID                    FUNCTION:NAME
       0      1                           :BEGIN   Hello world        0      1                           :BEGIN   Hello world
       
   The same script could be executed as a one liner on the shell, using
   
       dtrace -n 'BEGIN { trace("Hello world"); exit(0); }'
   
 ## A more complex example  ## A more complex example
   
Line 148  made by a process Line 151  made by a process
 - `execsnoop` - snoop on execution of processes as they occur  - `execsnoop` - snoop on execution of processes as they occur
 - `opensnoop` - snoop on openning of files as they occur  - `opensnoop` - snoop on openning of files as they occur
 - `procsystime` -  print process system call time details.  - `procsystime` -  print process system call time details.
   
   ## Troubleshooting
   
   The Compact C Type Format (CTF) has a 2^15 limit on types which can overflow, this prevents DTrace from
   working correctly.
   
   Check the number of types using `ctfdump` e.g
   
       ctfdump -S /netbsd
   
   Note the line which states `total number of types`, the value should by less than 32768.
   
   If overflow is not an issue, `libdtrace(3)` can provide some insight into what is going on via an
   environment variable. Define `DTRACE_DEBUG` before tracing.
   
        env DTRACE_DEBUG= execsnoop
   
Removed from v.1.26  
changed lines
  Added in v.1.29

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