strace(1M) System Administration Commands strace(1M)NAMEstrace - print STREAMS trace messages
SYNOPSISstrace [ mid sid level...]
DESCRIPTIONstrace 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 mes‐
sages 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 administra‐
tor (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 mod‐
ule 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 ALSOattributes(5), log(7D)
STREAMS Programming Guide
NOTES
· There is no restriction to the number of strace processes opening
the STREAMS log driver at a time.
· 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 5.10 4 Oct 1994 strace(1M)
