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-rw-r--r--doc/CrtInterp.331
1 files changed, 16 insertions, 15 deletions
diff --git a/doc/CrtInterp.3 b/doc/CrtInterp.3
index b0dfc50..14679a6 100644
--- a/doc/CrtInterp.3
+++ b/doc/CrtInterp.3
@@ -5,7 +5,7 @@
'\" See the file "license.terms" for information on usage and redistribution
'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
'\"
-'\" RCS: @(#) $Id: CrtInterp.3,v 1.7 2002/06/26 11:50:52 msofer Exp $
+'\" RCS: @(#) $Id: CrtInterp.3,v 1.8 2008/07/08 12:34:58 dkf Exp $
'\"
.so man.macros
.TH Tcl_CreateInterp 3 7.5 Tcl "Tcl Library Procedures"
@@ -28,25 +28,24 @@ int
.AP Tcl_Interp *interp in
Token for interpreter to be destroyed.
.BE
-
.SH DESCRIPTION
.PP
\fBTcl_CreateInterp\fR creates a new interpreter structure and returns
-a token for it. The token is required in calls to most other Tcl
+a token for it. The token is required in calls to most other Tcl
procedures, such as \fBTcl_CreateCommand\fR, \fBTcl_Eval\fR, and
\fBTcl_DeleteInterp\fR.
Clients are only allowed to access a few of the fields of
-Tcl_Interp structures; see the \fBTcl_Interp\fR
+Tcl_Interp structures; see the \fBTcl_Interp\fR
and \fBTcl_CreateCommand\fR man pages for details.
The new interpreter is initialized with the built-in Tcl commands
-and with the variables documented in tclvars(n). To bind in
+and with the variables documented in tclvars(n). To bind in
additional commands, call \fBTcl_CreateCommand\fR.
.PP
\fBTcl_DeleteInterp\fR marks an interpreter as deleted; the interpreter
will eventually be deleted when all calls to \fBTcl_Preserve\fR for it have
been matched by calls to \fBTcl_Release\fR. At that time, all of the
resources associated with it, including variables, procedures, and
-application-specific command bindings, will be deleted. After
+application-specific command bindings, will be deleted. After
\fBTcl_DeleteInterp\fR returns any attempt to use \fBTcl_Eval\fR on the
interpreter will fail and return \fBTCL_ERROR\fR. After the call to
\fBTcl_DeleteInterp\fR it is safe to examine the interpreter's result,
@@ -66,7 +65,6 @@ between when only the memory the callback is responsible for is being
deleted and when the whole interpreter is being deleted. In the former case
the callback may recreate the data being deleted, but this would lead to an
infinite loop if the interpreter were being deleted.
-
.SH "INTERPRETERS AND MEMORY MANAGEMENT"
.PP
\fBTcl_DeleteInterp\fR can be called at any time on an interpreter that may
@@ -86,14 +84,16 @@ the last call to \fBTcl_Preserve\fR is matched by a call to
The rules for when the user of an interpreter must call \fBTcl_Preserve\fR
and \fBTcl_Release\fR are simple:
.TP
-Interpreters Passed As Arguments
+\fBInterpreters Passed As Arguments\fR
+.
Functions that are passed an interpreter as an argument can safely use the
interpreter without any special protection. Thus, when you write an
extension consisting of new Tcl commands, no special code is needed to
protect interpreters received as arguments. This covers the majority of all
uses.
.TP
-Interpreter Creation And Deletion
+\fBInterpreter Creation And Deletion\fR
+.
When a new interpreter is created and used in a call to \fBTcl_Eval\fR,
\fBTcl_VarEval\fR, \fBTcl_GlobalEval\fR, \fBTcl_SetVar\fR, or
\fBTcl_GetVar\fR, a pair of calls to \fBTcl_Preserve\fR and
@@ -104,13 +104,16 @@ it is no longer needed, call \fBTcl_InterpDeleted\fR to test if some other
code already called \fBTcl_DeleteInterp\fR; if not, call
\fBTcl_DeleteInterp\fR before calling \fBTcl_Release\fR in your own code.
.TP
-Retrieving An Interpreter From A Data Structure
+\fBRetrieving An Interpreter From A Data Structure\fR
+.
When an interpreter is retrieved from a data structure (e.g. the client
-data of a callback) for use in \fBTcl_Eval\fR, \fBTcl_VarEval\fR,
-\fBTcl_GlobalEval\fR, \fBTcl_SetVar\fR, or \fBTcl_GetVar\fR, a pair of
+data of a callback) for use in one of the evaluation functions
+(\fBTcl_Eval\fR, \fBTcl_VarEval\fR, \fBTcl_GlobalEval\fR, \fBTcl_EvalObjv\fR,
+etc.) or variable access functions (\fBTcl_SetVar\fR, \fBTcl_GetVar\fR,
+\fBTcl_SetVar2Ex\fR, etc.), a pair of
calls to \fBTcl_Preserve\fR and \fBTcl_Release\fR should be wrapped around
all uses of the interpreter; it is unsafe to reuse the interpreter once
-\fBTcl_Release\fR has been called. If an interpreter is stored inside a
+\fBTcl_Release\fR has been called. If an interpreter is stored inside a
callback data structure, an appropriate deletion cleanup mechanism should
be set up by the code that creates the data structure so that the
interpreter is removed from the data structure (e.g. by setting the field
@@ -121,9 +124,7 @@ reused.
All uses of interpreters in Tcl and Tk have already been protected.
Extension writers should ensure that their code also properly protects any
additional interpreters used, as described above.
-
.SH "SEE ALSO"
Tcl_Preserve(3), Tcl_Release(3)
-
.SH KEYWORDS
command, create, delete, interpreter