strace(1M)						  System Administration Commands						strace(1M)

NAME

       strace - print STREAMS trace messages

SYNOPSIS

       strace [mid sid level]...

DESCRIPTION

       strace  without	arguments  writes all STREAMS event trace messages from all drivers and modules to its standard output. These messages are
       obtained from the STREAMS log driver (see log(7D)). If arguments are provided, they must be in triplets of the form mid, sid, level,  where
       mid  is	a  STREAMS  module  ID number, sid is a sub-ID number,	and level is a tracing priority level. Each triplet indicates that tracing
       messages are to be received from the given module/driver, sub-ID (usually indicating minor device), and priority level equal  to,  or  less
       than the given level. The token all may be used for any member to indicate no restriction for that attribute.

       The format of each trace message output is:

       <seq> <time> <ticks> <level> <flags> <mid> <sid> <text>

       <seq>	  trace sequence number

       <time>	  time of message in hh:mm:ss

       <ticks>	  time of message in machine ticks since boot

       <level>	  tracing priority level

       <flags>	  E  :	message  is  also in the error log F : indicates a fatal error N : mail was sent to the system administrator (hardcoded as
		  root)

       <mid>	  module  ID number of source

       <sid>	  sub-ID number of source

       <text>	  formatted text of the trace message

       Once initiated, strace will continue to execute until terminated by the user.

EXAMPLES

       Example 1 A sample output of the strace command:

       The following example outputs all trace messages from the module or driver whose module	ID is  41:

	 strace  41 all all

       The following example outputs those trace messages from driver or module  ID 41 with  sub-IDs 0, 1, or  2:

	 strace  41 0 1  41 1 1  41 2 0

       Messages from sub-IDs  0 and  1 must have  a tracing level less than or equal to  1. Those from sub-ID  2 must have a tracing level of  0.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWcsu			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       attributes(5), log(7D)

NOTES

	   o	  There is no restriction to the number of strace processes opening the  STREAMS log driver at a time.

	   o	  The log-driver records the list of the triplets specified in the command invocation, and compares each potential  trace  message
		  against this list to decide if it should be formatted and sent up to the strace process. Hence, long lists of triplets will have
		  a greater impact on overall STREAMS performance. Running strace will have the most impact on	the  timing  of  the  modules  and
		  drivers  generating  the  trace  messages  that  are sent to the strace process. If trace messages are generated faster than the
		  strace process can handle them,  some of the messages will be lost. This last case can be determined by examining  the  sequence
		  numbers on the trace messages output.

SunOS 5.11							    4 Oct 1994								strace(1M)