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-rw-r--r--doc/SetResult.3101
1 files changed, 66 insertions, 35 deletions
diff --git a/doc/SetResult.3 b/doc/SetResult.3
index 4bb9101..1f86340 100644
--- a/doc/SetResult.3
+++ b/doc/SetResult.3
@@ -9,7 +9,7 @@
.so man.macros
.BS
.SH NAME
-Tcl_SetObjResult, Tcl_GetObjResult, Tcl_SetResult, Tcl_GetStringResult, Tcl_AppendResult, Tcl_AppendResultVA, Tcl_AppendElement, Tcl_ResetResult, Tcl_FreeResult \- manipulate Tcl result
+Tcl_SetObjResult, Tcl_GetObjResult, Tcl_SetResult, Tcl_GetStringResult, Tcl_AppendResult, Tcl_AppendResultVA, Tcl_AppendElement, Tcl_ResetResult, Tcl_TransferResult, Tcl_FreeResult \- manipulate Tcl result
.SH SYNOPSIS
.nf
\fB#include <tcl.h>\fR
@@ -28,21 +28,25 @@ const char *
.sp
\fBTcl_AppendResultVA\fR(\fIinterp, argList\fR)
.sp
-\fBTcl_AppendElement\fR(\fIinterp, element\fR)
-.sp
\fBTcl_ResetResult\fR(\fIinterp\fR)
.sp
+.VS 8.6
+\fBTcl_TransferResult\fR(\fIsourceInterp, result, targetInterp\fR)
+.VE 8.6
+.sp
+\fBTcl_AppendElement\fR(\fIinterp, element\fR)
+.sp
\fBTcl_FreeResult\fR(\fIinterp\fR)
.SH ARGUMENTS
-.AS Tcl_FreeProc freeProc out
+.AS Tcl_FreeProc sourceInterp out
.AP Tcl_Interp *interp out
Interpreter whose result is to be modified or read.
.AP Tcl_Obj *objPtr in
-Object value to become result for \fIinterp\fR.
+Tcl value to become result for \fIinterp\fR.
.AP char *result in
String value to become result for \fIinterp\fR or to be
appended to the existing result.
-.AP char *element in
+.AP "const char" *element in
String value to append as a list element
to the existing result of \fIinterp\fR.
.AP Tcl_FreeProc *freeProc in
@@ -52,37 +56,50 @@ Address of procedure to call to release storage at
.AP va_list argList in
An argument list which must have been initialized using
\fBva_start\fR, and cleared using \fBva_end\fR.
+.AP Tcl_Interp *sourceInterp in
+.VS 8.6
+Interpreter that the result and error information should be copied from.
+.VE 8.6
+.AP Tcl_Interp *targetInterp in
+.VS 8.6
+Interpreter that the result and error information should be copied to.
+.VE 8.6
+.AP int result in
+.VS 8.6
+If \fBTCL_OK\fR, only copy the result. If \fBTCL_ERROR\fR, copy the error
+information as well.
+.VE 8.6
.BE
.SH DESCRIPTION
.PP
The procedures described here are utilities for manipulating the
result value in a Tcl interpreter.
-The interpreter result may be either a Tcl object or a string.
+The interpreter result may be either a Tcl value or a string.
For example, \fBTcl_SetObjResult\fR and \fBTcl_SetResult\fR
-set the interpreter result to, respectively, an object and a string.
+set the interpreter result to, respectively, a value and a string.
Similarly, \fBTcl_GetObjResult\fR and \fBTcl_GetStringResult\fR
-return the interpreter result as an object and as a string.
-The procedures always keep the string and object forms
+return the interpreter result as a value and as a string.
+The procedures always keep the string and value forms
of the interpreter result consistent.
For example, if \fBTcl_SetObjResult\fR is called to set
-the result to an object,
+the result to a value,
then \fBTcl_GetStringResult\fR is called,
-it will return the object's string value.
+it will return the value's string representation.
.PP
\fBTcl_SetObjResult\fR
arranges for \fIobjPtr\fR to be the result for \fIinterp\fR,
replacing any existing result.
-The result is left pointing to the object
+The result is left pointing to the value
referenced by \fIobjPtr\fR.
\fIobjPtr\fR's reference count is incremented
since there is now a new reference to it from \fIinterp\fR.
-The reference count for any old result object
-is decremented and the old result object is freed if no
+The reference count for any old result value
+is decremented and the old result value is freed if no
references to it remain.
.PP
-\fBTcl_GetObjResult\fR returns the result for \fIinterp\fR as an object.
-The object's reference count is not incremented;
-if the caller needs to retain a long-term pointer to the object
+\fBTcl_GetObjResult\fR returns the result for \fIinterp\fR as a value.
+The value's reference count is not incremented;
+if the caller needs to retain a long-term pointer to the value
they should use \fBTcl_IncrRefCount\fR to increment its reference count
in order to keep it from being freed too early or accidentally changed.
.PP
@@ -98,19 +115,19 @@ and \fBTcl_SetResult\fR
re-initializes \fIinterp\fR's result to point to an empty string.
.PP
\fBTcl_GetStringResult\fR returns the result for \fIinterp\fR as a string.
-If the result was set to an object by a \fBTcl_SetObjResult\fR call,
-the object form will be converted to a string and returned.
-If the object's string representation contains null bytes,
+If the result was set to a value by a \fBTcl_SetObjResult\fR call,
+the value form will be converted to a string and returned.
+If the value's string representation contains null bytes,
this conversion will lose information.
For this reason, programmers are encouraged to
-write their code to use the new object API procedures
+write their code to use the new value API procedures
and to call \fBTcl_GetObjResult\fR instead.
.PP
\fBTcl_ResetResult\fR clears the result for \fIinterp\fR
and leaves the result in its normal empty initialized state.
-If the result is an object,
+If the result is a value,
its reference count is decremented and the result is left
-pointing to an unshared object representing an empty string.
+pointing to an unshared value representing an empty string.
If the result is a dynamically allocated string, its memory is free*d
and the result is left as a empty string.
\fBTcl_ResetResult\fR also clears the error state managed by
@@ -137,12 +154,20 @@ call; the last argument in the list must be a NULL pointer.
.PP
\fBTcl_AppendResultVA\fR is the same as \fBTcl_AppendResult\fR except that
instead of taking a variable number of arguments it takes an argument list.
-.SH "OLD STRING PROCEDURES"
+.PP
+.VS 8.6
+\fBTcl_TransferResult\fR moves a result from one interpreter to another,
+optionally (dependent on the \fIresult\fR parameter) including the error
+information dictionary as well. The interpreters must be in the same thread.
+The source interpreter will have its result reset by this operation.
+.VE 8.6
+.SH "DEPRECATED INTERFACES"
+.SS "OLD STRING PROCEDURES"
.PP
Use of the following procedures (is deprecated
since they manipulate the Tcl result as a string.
Procedures such as \fBTcl_SetObjResult\fR
-that manipulate the result as an object
+that manipulate the result as a value
can be significantly more efficient.
.PP
\fBTcl_AppendElement\fR is similar to \fBTcl_AppendResult\fR in
@@ -172,16 +197,19 @@ It also sets \fIinterp->freeProc\fR to zero, but does not
change \fIinterp->result\fR or clear error state.
\fBTcl_FreeResult\fR is most commonly used when a procedure
is about to replace one result value with another.
-.SH "DIRECT ACCESS TO INTERP->RESULT IS DEPRECATED"
+.SS "DIRECT ACCESS TO INTERP->RESULT"
.PP
It used to be legal for programs to
directly read and write \fIinterp->result\fR
-to manipulate the interpreter result.
-Direct access to \fIinterp->result\fR is now strongly deprecated
-because it can make the result's string and object forms inconsistent.
-Programs should always read the result
-using the procedures \fBTcl_GetObjResult\fR or \fBTcl_GetStringResult\fR,
-and write the result using \fBTcl_SetObjResult\fR or \fBTcl_SetResult\fR.
+to manipulate the interpreter result. The Tcl headers no longer
+permit this access by default, and C code still doing this must
+be updated to use supported routines \fBTcl_GetObjResult\fR,
+\fBTcl_GetStringResult\fR, \fBTcl_SetObjResult\fR, and \fBTcl_SetResult\fR.
+As a migration aid, access can be restored with the compiler directive
+.CS
+#define USE_INTERP_RESULT
+.CE
+but this is meant only to offer life support to otherwise dead code.
.SH "THE TCL_FREEPROC ARGUMENT TO TCL_SETRESULT"
.PP
\fBTcl_SetResult\fR's \fIfreeProc\fR argument specifies how
@@ -213,12 +241,15 @@ This allows applications to use non-standard storage allocators.
When Tcl no longer needs the storage for the string, it will
call \fIfreeProc\fR. \fIFreeProc\fR should have arguments and
result that match the type \fBTcl_FreeProc\fR:
+.PP
.CS
-typedef void Tcl_FreeProc(char *\fIblockPtr\fR);
+typedef void \fBTcl_FreeProc\fR(
+ char *\fIblockPtr\fR);
.CE
+.PP
When \fIfreeProc\fR is called, its \fIblockPtr\fR will be set to
the value of \fIresult\fR passed to \fBTcl_SetResult\fR.
.SH "SEE ALSO"
Tcl_AddErrorInfo, Tcl_CreateObjCommand, Tcl_SetErrorCode, Tcl_Interp
.SH KEYWORDS
-append, command, element, list, object, result, return value, interpreter
+append, command, element, list, value, result, return value, interpreter