The START command starts tracing on one or more specified tracepoints. Format: START [tracepoint-name,...] [/qualifiers] Only one trace session at a time can collect data from the local system, though it can collect more than one tracepoint at a time. For remote tracing, data can be collected from only one remote server at a time.
1 – Parameters
A tracepoint name has the following general form: [node-name ["user-name password"]::]"tracepoint-name" node-name Specifies the node name of a remote system. You must specify a node name when starting a remote tracepoint. user-name Specifies the user name associated with the remote CTF object. You must specify this user name if the remote CTF object is protected. password Specifies the password associated with the remote CTF object. You must specify this password if the remote CTF object is protected. tracepoint-name Specifies the name of a tracepoint that you want to trace. If you are specifying more than one tracepoint, separate each tracepoint name with a comma.
2 – Command qualifiers
The following qualifiers are relevant only for detached tracing: /BLOCKS /OUTPUT /PRIORITY /PROCESS_NAME /VERSION_LIMIT The following qualifiers are relevant only for live tracing: /BRIEF /DATA /DISPLAY /FULL /NAME /PAGE /PROTOCOL /REVERSE /SAVE_BUFFER_SIZE /SELECT /TRUNCATE /WIDTH The following qualifiers are relevant for both detached and live tracing: /BUFFER_SIZE /CAPTURE_SIZE /COLLECT /FILTER /LIVE /MAXIMUM_BUFFERS /TIME_OUT
3 /BLOCKS
/BLOCKS=n Specifies the size, in blocks, of the trace file to which trace records from the specified tracepoints are written. If a trace file reaches its maximum size, a new version of the trace file is created. The default file size is 200 blocks. The minimum file size is 20 blocks.
4 /BRIEF
/BRIEF Specifies that a single-line analysis of the protocol data in each trace record is displayed. This qualifier is effective only if the relevant protocol analysis routines support abbreviated analysis of protocol data. The default is /BRIEF.
5 /BUFFER_SIZE
/BUFFER_SIZE=n Specifies the size, in bytes, of each CTF internal trace buffer (used for remote tracing only). You can set this value larger to enable CTF to include more trace records in a single buffer. The default buffer size is 512 bytes. The minimum buffer size is 68 bytes.
6 /CAPTURE_SIZE
/CAPTURE_SIZE=n Specifies the amount of data, in bytes, captured in each trace record. The default data size is 140 bytes. The minimum data size is 0. The maximum data size is 5000 bytes.
7 /COLLECT
/COLLECT /NOCOLLECT NOCOLLECT prevents collected trace records being written to a trace file or displayed on your terminal until you issue a COLLECT command. The buffer into which trace records are collected is used as a circular buffer; when the buffer is full, new trace records overwrite the oldest trace records. The default is /COLLECT.
8 /DATA
/DATA=(data-type,...)
/NODATA
Use /DATA to specify the format(s) of the output.
Valid data-types are:
DECIMAL, OCTAL, HEXADECIMAL, ASCII and EBCDIC
9 /DISPLAY
/DISPLAY=(field,...)
/NODISPLAY
Specifies which fields (apart from the protocol data itself)
in a trace record are displayed.
The fields that can be displayed are:
[NO]ALL All the fields shown below are displayed.
[NO]CONTEXT Tracepoint-specific information.
[NO]EVENT The event code.
[NO]FUNCTION_CODE The tracepoint-specific function code of
the operation being traced.
[NO]NAME The name of the tracepoint from which the
trace record was collected. Names longer
than 16 characters will be truncated on
the right.
[NO]SIZE The original size of the trace data, in
bytes.
[NO]STATUS If the value in this field is non-zero, it
is the current status of the operation
being traced.
[NO]TIME The time at which the trace record was
collected.
The default display is:
TIME
EVENT
SIZE
10 /FILTER
/FILTER=(event-code,...) /NOFILTER Specifies a filter for trace records. A trace record is collected only if its event code is one of those specified in the filter. This filter overrides the current filter, if any. You cannot specify this qualifier with /SELECT. The default is /NOFILTER, meaning that all trace records are collected.
11 /FULL
/FULL
Specifies that a multi-line analysis of the protocol data in
each trace record is produced. This qualifier is effective
only if the relevant protocol analysis routines support full
analysis of protocol data.
If you do not specify /FULL, the default is /BRIEF.
12 /LIVE
/LIVE /NOLIVE Specifies whether live or detached tracing is performed on the specified tracepoints. The default is /NOLIVE, indicating that detached tracing is performed.
13 /MAXIMUM_BUFFERS
/MAXIMUM_BUFFERS=n Specifies the maximum number of CTF internal trace buffers. The default is 5.
14 /NAME
/NAME=instance-name Specifies the instance part of a tracepoint name. A trace record is displayed only if it came from the specified tracepoint. If you specify only the first part of an instance name, trace records are displayed from all tracepoints whose name begins with this string. The default is to display trace records from all active tracepoints.
15 /OUTPUT
/OUTPUT=filename Specifies the name of the trace file to which trace records are written. The default trace file is the file CTF$TRACE.DAT in your default directory.
16 /PAGE
/PAGE=lines-per-page Specifies the number of lines per page when writing output to a file. This qualifier has no effect if trace records are being displayed on your terminal. The default is defined by the logical name SYS$LP_LINES, which usually has the value 66.
17 /PRIORITY
/PRIORITY=priority Specifies the base priority for the trace server process that writes trace records to the trace file. The default is 8. The lowest is 0 and the highest is 15.
18 /PROCESS_NAME
/PROCESS_NAME=process-name Specifies the name to be given to the trace server process that is created to write trace records to the trace file. The default process name is username$CTF.
19 /PROTOCOL
/PROTOCOL=(protocol-identifier,...) /NOPROTOCOL Specifies the type of analysis performed on each trace record. The protocol data in each trace record is analyzed for each of the protocols listed in the /PROTOCOL qualifier, in the order in which they are specified. If you do not specify this qualifier, only the protocol data supplied at the protocol level of the originating tracepoint is analyzed; protocol data from lower levels is displayed, unanalyzed, as user data. If you specify /NOPROTOCOL, no analysis is performed on the protocol data in the trace record; it is all presented as user data.
20 /REVERSE
/REVERSE /NOREVERSE Specifies that received data will be displayed in reverse video, and titles will be displayed in bold. The default is /REVERSE.
21 /SAVE_BUFFER_SIZE
/SAVE_BUFFER_SIZE=n Specifies how many screens of saved lines of data will be kept. These lines can be examined by using the NEXT and BACK commands. The default is 30 screens. The minimum is 1 screen. The maximum is 1000 screens.
22 /SELECT
/SELECT=(protocol-identifier,...) Specifies which protocol analyses are to be displayed. This qualifier is only useful if you have used the /PROTOCOL qualifier to request multiple protocol analysis of a trace record. The default is to display all the protocol analyses requested by the /PROTOCOL qualifier.
23 /TIME_OUT
/TIME_OUT=n Specifies the interval, in seconds, for which CTF support waits before flushing partially filled buffers to the the trace server process. The default for detached tracing is 30 seconds; the default for live tracing is 5 seconds.
24 /TRUNCATE
/TRUNCATE /NOTRUNCATE Specifies whether data that will not fit on one line is truncated or continued on the next line. The default is /NOTRUNCATE.
25 /VERSION_LIMIT
/VERSION_LIMIT=n Specifies the number of versions of the trace file to keep. When this many versions have been created, each new version of the trace file causes the oldest current version to be deleted. The default is 10.
26 /WIDTH
/WIDTH=n Specifies the width of the output. The default is the width of your terminal screen.
27 – Examples
CTF> START "ROUTING CIRCUIT UNA-0" Starts detached tracing at the specified local tracepoint. Trace records are written to CTF$TRACE.DAT in your default directory. The trace server process that collects trace records is username$CTF. CTF> START NODEB"netman netmanpw"::"ROUTING CIRCUIT UNA-2" Starts detached tracing at the specified remote tracepoint. CTF> START "ROUTING CIRCUIT UNA-1" /OUT=UNA-1/PROC=UNA1PROC Starts detached tracing at the specified local tracepoint. Trace records are written to the file UNA-1.DAT, and the name of the trace server process that is created to collect trace records is UNA1PROC. CTF> START "ROUTING CIRCUIT UNA-3" /LIVE/FULL Starts live tracing at the specified local tracepoint. A full analysis of each trace record is displayed on your screen.