strace(1M)                                                       strace(1M)




 NAME    [Toc]    [Back]
      strace - write STREAMS event trace messages to standard output

 SYNOPSIS    [Toc]    [Back]
      strace [ mod sub pri ] ...

 DESCRIPTION    [Toc]    [Back]
      strace gets STREAMS event trace messages from STREAMS drivers and
      modules via the STREAMS log driver (strlog(7)), and writes these
      messages to standard output.  By default, strace without arguments
      writes all STREAMS trace messages from all drivers and modules.
      strace with command-line arguments limits the trace messages received.

      The arguments, which must be specified in groups of three, are:

           mod  Specifies the STREAMS module identification number from the
                streamtab entry.

           sub  Specifies a subidentification number (often corresponding to
                a minor device).

           pri  Specifies a tracing priority level.  strace gets messages of
                a level equal to or less than the value specified by pri.
                Only positive integer values are allowed.

      The value all can be used for any argument in the strace command line
      to indicate that there are no restrictions for that argument.

      Multiple sets of the three arguments can be specified to obtain the
      messages from more than one driver or module.

      Only one strace process can open the STREAMS log driver at a time.

      When strace is invoked, the log driver compares the sets of command
      line arguments with actual trace messages, returning only messages
      that satisfy the specified criteria.

      STREAMS event trace messages have the following format:

           seq time tick pri ind mod sub text

      Components are interpreted as follows:

           seq  Trace event sequence number.

           time Time the message was sent expressed in hh:mm:ss.

           tick Time the message was sent expressed in machine ticks since
                the last boot.





 Hewlett-Packard Company            - 1 -   HP-UX 11i Version 2: August 2003






 strace(1M)                                                       strace(1M)




           pri  Tracing priority level as defined by the STREAMS driver or
                module that originates the messages.

           ind  Can be any combination of the following three message
                indicators:

                     E    The message has also been saved in the error log.

                     F    The message signaled a fatal error.

                     N    The message has also been mailed to the system
                          administrator.

           mod  Module identification number of the trace message source.

           sub  Subidentification number of the trace message source.

           text Trace message text.

      strace runs until terminated by the user.

 EXAMPLES    [Toc]    [Back]
      Display all trace messages received from the driver or module
      identified by mod 28:

           strace 28 all all

      Display trace messages of any tracing priority level from the driver
      or module identified by mod 28 and its minor devices identified by the
      sub 2, 3, or 4:

           strace  28 2 all  28 3 all  28 4 all

      Display the trace messages from the same driver or module and subs but
      limit the priority levels to 0 for subs 2 and 3; 1 for sub 4, driver
      or module 28:

           strace  28 2 0  28 3 0  28 4 1

 WARNINGS    [Toc]    [Back]
      Running strace with several sets of arguments can impair STREAMS
      performance, particularly for those modules and drivers that are
      sending the messages.

      Also be aware that strace may not be able to handle a large number of
      messages.  If drivers and modules return messages to strace too
      quickly, some may be lost.

 FILES    [Toc]    [Back]
      /usr/lib/nls/msg/C/strace.cat                     NLS catalog for
                                                        strace.



 Hewlett-Packard Company            - 2 -   HP-UX 11i Version 2: August 2003






 strace(1M)                                                       strace(1M)




 SEE ALSO    [Toc]    [Back]
      strclean(1M), strerr(1M), strlog(7).


 Hewlett-Packard Company            - 3 -   HP-UX 11i Version 2: August 2003