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-rw-r--r--doc/trace.n15
1 files changed, 15 insertions, 0 deletions
diff --git a/doc/trace.n b/doc/trace.n
index 97fbdba..4ae7e19 100644
--- a/doc/trace.n
+++ b/doc/trace.n
@@ -54,9 +54,11 @@ execute them.
When the trace triggers, depending on the operations being traced, a number of
arguments are appended to \fIcommandPrefix\fR so that the actual command is as
follows:
+.PP
.CS
\fIcommandPrefix oldName newName op\fR
.CE
+.PP
\fIOldName\fR and \fInewName\fR give the traced command's current (old) name,
and the name to which it is being renamed (the empty string if this is a
.QW delete
@@ -121,9 +123,11 @@ number of arguments are appended to \fIcommandPrefix\fR so that the actual
command is as follows:
.PP
For \fBenter\fR and \fBenterstep\fR operations:
+.PP
.CS
\fIcommandPrefix command-string op\fR
.CE
+.PP
\fICommand-string\fR gives the complete current command being
executed (the traced command for a \fBenter\fR operation, an
arbitrary command for a \fBenterstep\fR operation), including
@@ -137,9 +141,11 @@ course when the command is subsequently executed, an
error will occur.
.PP
For \fBleave\fR and \fBleavestep\fR operations:
+.PP
.CS
\fIcommandPrefix command-string code result op\fR
.CE
+.PP
\fICommand-string\fR gives the complete current command being
executed (the traced command for a \fBenter\fR operation, an
arbitrary command for a \fBenterstep\fR operation), including
@@ -217,9 +223,11 @@ interpreter in which to execute them.
.PP
When the trace triggers, three arguments are appended to
\fIcommandPrefix\fR so that the actual command is as follows:
+.PP
.CS
\fIcommandPrefix name1 name2 op\fR
.CE
+.PP
\fIName1\fR and \fIname2\fR give the name(s) for the variable
being accessed: if the variable is a scalar then \fIname1\fR
gives the variable's name and \fIname2\fR is an empty string;
@@ -368,9 +376,11 @@ future version of Tcl. They use an older syntax in which \fBarray\fR,
list, but simply a string concatenation of the operations, such as
\fBrwua\fR.
.SH EXAMPLES
+.PP
Print a message whenever either of the global variables \fBfoo\fR and
\fBbar\fR are updated, even if they have a different local name at the
time (which can be done with the \fBupvar\fR command):
+.PP
.CS
proc tracer {varname args} {
upvar #0 $varname var
@@ -382,6 +392,7 @@ proc tracer {varname args} {
.PP
Ensure that the global variable \fBfoobar\fR always contains the
product of the global variables \fBfoo\fR and \fBbar\fR:
+.PP
.CS
proc doMult args {
global foo bar foobar
@@ -393,6 +404,7 @@ proc doMult args {
.PP
Print a trace of what commands are executed during the processing of a Tcl
procedure:
+.PP
.CS
proc x {} { y }
proc y {} { z }
@@ -409,3 +421,6 @@ x
set(n), unset(n)
.SH KEYWORDS
read, command, rename, variable, write, trace, unset
+.\" Local Variables:
+.\" mode: nroff
+.\" End: