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strace(8)
NAME
  strace - Writes STREAMS event trace messages to standard output

SYNOPSIS
  /usr/sbin/strace [mod_ID sub_ID pri_level]

OPERANDS
  mod_ID
      Specifies the STREAMS module identification number.

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

  pri_level
      Specifies a tracing priority level.  The strace command will get
      messages of a level equal to or less than the value in the pri_level
      argument. The value of the argument must be a nonnegative integer.

DESCRIPTION
  The strace command gets STREAMS event trace messages from STREAMS drivers
  and modules via the STREAMS log driver (strlog), and writes these messages
  to standard output. You can limit the messages strace receives by
  specifying arguments to the command. All three operands must be specified
  together.

  You can specify all as the value for any of the arguments in the strace
  command line. The value all indicates that there are no restrictions for
  that argument.

  You can also specify multiple sets of the command's three arguments to
  obtain the messages from more than one driver or module.

  More than one strace process can open the STREAMS log driver at a time.
  When you invoke strace, the log driver compares the sets of arguments from
  the command line with actual trace messages, returning the messages that
  satisfy the criteria.

  STREAMS event trace messages have the following format:

       seqnum  stdtime	tickstime  pri_level  ntfycode	mod_ID	sub_ID	msgtext

  seqnum
      The event trace sequence number.

  stdtime
      The time the message was sent, in the format hh:mm:ss.

  tickstime
      The time the message was sent, measured in machine ticks since the last
      boot.

  pri_level
      The tracing priority level as defined by the STREAMS driver or module
      that originates the messages.

  ntfycode
      Can be either of the following indicators:

      E	  Indicates that the message has also been saved in the error log.

      F	  Indicates that the message signaled a fatal error.

  mod_ID
      The module identification number of the trace message source.

  sub_ID
      The subidentification number of the trace message source.

  msgtext
      The trace message text.

  The strace command runs until terminated by the user.

RESTRICTIONS
  Running strace with several sets of arguments can negatively affect STREAMS
  performance, particularly for those modules and drivers 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.

EXAMPLES
   1.  To display all trace messages received from the driver or module
       identified by mod_ID 28, enter:
	    % strace 28 all all

   2.  To display those trace messages from the driver or module identified
       by mod_ID 28 and its minor devices identified by the sub_IDs 2, 3, and
       4, enter:
	    % strace  28 2 all	28 3 all  28 4 all

       This command line causes messages of any tracing priority level to be
       displayed.

   3.  To display the trace messages from the same driver or module and
       sub_IDs, but limited to certain priority levels, enter:
	    % strace  28 2 0  28 3 0  28 4 1

       This command line specifies that messages from driver or module 28 and
       sub_IDs 2 and 3 must have a tracing priority of 0, and those from
       sub_ID 4 must have a tracing priority equal to or less than 1.

SEE ALSO
  Commands: strclean(8), strerr(8)

  Interfaces: strlog(7)

Index for Section 8

Alphabetical listing for S

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