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User & Date: dkf 2019-04-03 12:22:07
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2019-04-04
08:52
Split up tests to get better focus on what is being tested check-in: 84706f16ce user: dkf tags: tip-312-new
2019-04-03
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Docs check-in: 3c244a994e user: dkf tags: tip-312-new
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'\" See the file "license.terms" for information on usage and redistribution
'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
'\"
.TH Tcl_LinkVar 3 7.5 Tcl "Tcl Library Procedures"
.so man.macros
.BS
.SH NAME
Tcl_LinkVar, Tcl_UnlinkVar, Tcl_UpdateLinkedVar \- link Tcl variable to C variable
.SH SYNOPSIS
.nf
\fB#include <tcl.h>\fR
.sp
int
\fBTcl_LinkVar\fR(\fIinterp, varName, addr, type\fR)





.sp
\fBTcl_UnlinkVar\fR(\fIinterp, varName\fR)
.sp
\fBTcl_UpdateLinkedVar\fR(\fIinterp, varName\fR)
.SH ARGUMENTS
.AS Tcl_Interp writable
.AP Tcl_Interp *interp in
Interpreter that contains \fIvarName\fR.
Also used by \fBTcl_LinkVar\fR to return error messages.
.AP "const char" *varName in
Name of global variable.
.AP char *addr in
Address of C variable that is to be linked to \fIvarName\fR.
.AP int type in

Type of C variable.  Must be one of \fBTCL_LINK_INT\fR,
\fBTCL_LINK_UINT\fR, \fBTCL_LINK_CHAR\fR, \fBTCL_LINK_UCHAR\fR,
\fBTCL_LINK_SHORT\fR, \fBTCL_LINK_USHORT\fR, \fBTCL_LINK_LONG\fR,
\fBTCL_LINK_ULONG\fR, \fBTCL_LINK_WIDE_INT\fR,
\fBTCL_LINK_WIDE_UINT\fR, \fBTCL_LINK_FLOAT\fR,
\fBTCL_LINK_DOUBLE\fR, \fBTCL_LINK_BOOLEAN\fR, or












\fBTCL_LINK_STRING\fR, optionally OR'ed with \fBTCL_LINK_READ_ONLY\fR
to make Tcl variable read-only.




.BE
.SH DESCRIPTION
.PP
\fBTcl_LinkVar\fR uses variable traces to keep the Tcl variable
named by \fIvarName\fR in sync with the C variable at the address
given by \fIaddr\fR.
Whenever the Tcl variable is read the value of the C variable will
be returned, and whenever the Tcl variable is written the C
variable will be updated to have the same value.
\fBTcl_LinkVar\fR normally returns \fBTCL_OK\fR;  if an error occurs
while setting up the link (e.g. because \fIvarName\fR is the
name of array) then \fBTCL_ERROR\fR is returned and the interpreter's result
contains an error message.
.PP








The \fItype\fR argument specifies the type of the C variable,

and must have one of the following values, optionally OR'ed with
\fBTCL_LINK_READ_ONLY\fR:
.TP
\fBTCL_LINK_INT\fR

The C variable is of type \fBint\fR.
Any value written into the Tcl variable must have a proper integer
form acceptable to \fBTcl_GetIntFromObj\fR;  attempts to write
non-integer values into \fIvarName\fR will be rejected with
Tcl errors. Incomplete integer representations (like the empty
string, '+', '-' or the hex/octal/binary prefix) are accepted
as if they are valid too.
.TP
\fBTCL_LINK_UINT\fR

The C variable is of type \fBunsigned int\fR.
Any value written into the Tcl variable must have a proper unsigned
integer form acceptable to \fBTcl_GetWideIntFromObj\fR and in the
platform's defined range for the \fBunsigned int\fR type; attempts to
write non-integer values (or values outside the range) into
\fIvarName\fR will be rejected with Tcl errors. Incomplete integer
representations (like the empty string, '+', '-' or the hex/octal/binary
prefix) are accepted as if they are valid too.
.TP
\fBTCL_LINK_CHAR\fR

The C variable is of type \fBchar\fR.
Any value written into the Tcl variable must have a proper integer
form acceptable to \fBTcl_GetIntFromObj\fR and be in the range of the
\fBchar\fR datatype; attempts to write non-integer or out-of-range
values into \fIvarName\fR will be rejected with Tcl errors. Incomplete
integer representations (like the empty string, '+', '-' or the
hex/octal/binary prefix) are accepted as if they are valid too.






.TP







\fBTCL_LINK_UCHAR\fR

The C variable is of type \fBunsigned char\fR.
Any value written into the Tcl variable must have a proper unsigned
integer form acceptable to \fBTcl_GetIntFromObj\fR and in the
platform's defined range for the \fBunsigned char\fR type; attempts to
write non-integer values (or values outside the range) into
\fIvarName\fR will be rejected with Tcl errors. Incomplete integer
representations (like the empty string, '+', '-' or the hex/octal/binary
prefix) are accepted as if they are valid too.






.TP








\fBTCL_LINK_SHORT\fR

The C variable is of type \fBshort\fR.
Any value written into the Tcl variable must have a proper integer
form acceptable to \fBTcl_GetIntFromObj\fR and be in the range of the
\fBshort\fR datatype; attempts to write non-integer or out-of-range
values into \fIvarName\fR will be rejected with Tcl errors. Incomplete
integer representations (like the empty string, '+', '-' or the
hex/octal/binary prefix) are accepted as if they are valid too.
.TP
\fBTCL_LINK_USHORT\fR

The C variable is of type \fBunsigned short\fR.
Any value written into the Tcl variable must have a proper unsigned
integer form acceptable to \fBTcl_GetIntFromObj\fR and in the
platform's defined range for the \fBunsigned short\fR type; attempts to
write non-integer values (or values outside the range) into
\fIvarName\fR will be rejected with Tcl errors. Incomplete integer
representations (like the empty string, '+', '-' or the hex/octal/binary
prefix) are accepted as if they are valid too.
.TP
\fBTCL_LINK_LONG\fR

The C variable is of type \fBlong\fR.
Any value written into the Tcl variable must have a proper integer
form acceptable to \fBTcl_GetLongFromObj\fR; attempts to write
non-integer or out-of-range
values into \fIvarName\fR will be rejected with Tcl errors. Incomplete
integer representations (like the empty string, '+', '-' or the
hex/octal/binary prefix) are accepted as if they are valid too.
.TP
\fBTCL_LINK_ULONG\fR

The C variable is of type \fBunsigned long\fR.
Any value written into the Tcl variable must have a proper unsigned
integer form acceptable to \fBTcl_GetWideIntFromObj\fR and in the
platform's defined range for the \fBunsigned long\fR type; attempts to
write non-integer values (or values outside the range) into
\fIvarName\fR will be rejected with Tcl errors. Incomplete integer
representations (like the empty string, '+', '-' or the hex/octal/binary
prefix) are accepted as if they are valid too.
.TP
\fBTCL_LINK_DOUBLE\fR

The C variable is of type \fBdouble\fR.
Any value written into the Tcl variable must have a proper real
form acceptable to \fBTcl_GetDoubleFromObj\fR;  attempts to write
non-real values into \fIvarName\fR will be rejected with
Tcl errors. Incomplete integer or real representations (like the
empty string, '.', '+', '-' or the hex/octal/binary prefix) are
accepted as if they are valid too.
.TP
\fBTCL_LINK_FLOAT\fR

The C variable is of type \fBfloat\fR.
Any value written into the Tcl variable must have a proper real
form acceptable to \fBTcl_GetDoubleFromObj\fR and must be within the
range acceptable for a \fBfloat\fR; attempts to
write non-real values (or values outside the range) into
\fIvarName\fR will be rejected with Tcl errors. Incomplete integer
or real representations (like the empty string, '.', '+', '-' or
the hex/octal/binary prefix) are accepted as if they are valid too.
.TP
\fBTCL_LINK_WIDE_INT\fR


The C variable is of type \fBTcl_WideInt\fR (which is an integer type
at least 64-bits wide on all platforms that can support it.)
Any value written into the Tcl variable must have a proper integer
form acceptable to \fBTcl_GetWideIntFromObj\fR;  attempts to write
non-integer values into \fIvarName\fR will be rejected with
Tcl errors. Incomplete integer representations (like the empty
string, '+', '-' or the hex/octal/binary prefix) are accepted
as if they are valid too.
.TP
\fBTCL_LINK_WIDE_UINT\fR

The C variable is of type \fBTcl_WideUInt\fR (which is an unsigned
integer type at least 64-bits wide on all platforms that can support
it.)
Any value written into the Tcl variable must have a proper unsigned
integer form acceptable to \fBTcl_GetWideIntFromObj\fR (it will be
cast to unsigned);
.\" FIXME! Use bignums instead.
attempts to write non-integer values into \fIvarName\fR will be
rejected with Tcl errors. Incomplete integer representations (like
the empty string, '+', '-' or the hex/octal/binary prefix) are accepted
as if they are valid too.
.TP
\fBTCL_LINK_BOOLEAN\fR

The C variable is of type \fBint\fR.
If its value is zero then it will read from Tcl as
.QW 0 ;
otherwise it will read from Tcl as
.QW 1 .
Whenever \fIvarName\fR is
modified, the C variable will be set to a 0 or 1 value.
Any value written into the Tcl variable must have a proper boolean
form acceptable to \fBTcl_GetBooleanFromObj\fR;  attempts to write
non-boolean values into \fIvarName\fR will be rejected with
Tcl errors.
.TP
\fBTCL_LINK_STRING\fR

The C variable is of type \fBchar *\fR.
If its value is not NULL then it must be a pointer to a string
allocated with \fBTcl_Alloc\fR or \fBckalloc\fR.
Whenever the Tcl variable is modified the current C string will be
freed and new memory will be allocated to hold a copy of the variable's
new value.
If the C variable contains a NULL pointer then the Tcl variable
will read as
.QW NULL .

.PP
If the \fBTCL_LINK_READ_ONLY\fR flag is present in \fItype\fR then the
variable will be read-only from Tcl, so that its value can only be
changed by modifying the C variable.
Attempts to write the variable from Tcl will be rejected with errors.
.PP
\fBTcl_UnlinkVar\fR removes the link previously set up for the






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'\" See the file "license.terms" for information on usage and redistribution
'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
'\"
.TH Tcl_LinkVar 3 7.5 Tcl "Tcl Library Procedures"
.so man.macros
.BS
.SH NAME
Tcl_LinkArray, Tcl_LinkVar, Tcl_UnlinkVar, Tcl_UpdateLinkedVar \- link Tcl variable to C variable
.SH SYNOPSIS
.nf
\fB#include <tcl.h>\fR
.sp
int
\fBTcl_LinkVar\fR(\fIinterp, varName, addr, type\fR)
.sp
.VS "TIP 312"
int
\fBTcl_LinkArray\fR(\fIinterp, varName, addr, type, size\fR)
.VE "TIP 312"
.sp
\fBTcl_UnlinkVar\fR(\fIinterp, varName\fR)
.sp
\fBTcl_UpdateLinkedVar\fR(\fIinterp, varName\fR)
.SH ARGUMENTS
.AS Tcl_Interp varName in
.AP Tcl_Interp *interp in
Interpreter that contains \fIvarName\fR.
Also used by \fBTcl_LinkVar\fR to return error messages.
.AP "const char" *varName in
Name of global variable.
.AP void *addr in
Address of C variable that is to be linked to \fIvarName\fR.
.AP int type in
Type of C variable for \fBTcl_LinkVar\fR or type of array element for
\fBTcl_LinkArray\fR.  Must be one of \fBTCL_LINK_INT\fR,
\fBTCL_LINK_UINT\fR, \fBTCL_LINK_CHAR\fR, \fBTCL_LINK_UCHAR\fR,
\fBTCL_LINK_SHORT\fR, \fBTCL_LINK_USHORT\fR, \fBTCL_LINK_LONG\fR,
\fBTCL_LINK_ULONG\fR, \fBTCL_LINK_WIDE_INT\fR,
\fBTCL_LINK_WIDE_UINT\fR, \fBTCL_LINK_FLOAT\fR, \fBTCL_LINK_DOUBLE\fR,
\fBTCL_LINK_BOOLEAN\fR, or one of the extra ones listed below.
.sp
In \fBTcl_LinkVar\fR, the additional linked type \fBTCL_LINK_STRING\fR may be
used.
.sp
.VS "TIP 312"
In \fBTcl_LinkArray\fR, the additional linked types \fBTCL_LINK_CHARS\fR and
\fBTCL_LINK_BYTES\fR may be used.  \fBTCL_LINK_ALLOC\fR may also be OR'ed in
to tell Tcl to manage the storage for the array in the variable (that is, the
C variable is technically a pointer to an array, not the array itself).
.VE "TIP 312"
.sp
All the above for both functions may be
optionally OR'ed with \fBTCL_LINK_READ_ONLY\fR to make the Tcl
variable read-only.
.AP int size in
.VS "TIP 312"
The number of elements in the C array. Must be greater than zero.
.VE "TIP 312"
.BE
.SH DESCRIPTION
.PP
\fBTcl_LinkVar\fR uses variable traces to keep the Tcl variable
named by \fIvarName\fR in sync with the C variable at the address
given by \fIaddr\fR.
Whenever the Tcl variable is read the value of the C variable will
be returned, and whenever the Tcl variable is written the C
variable will be updated to have the same value.
\fBTcl_LinkVar\fR normally returns \fBTCL_OK\fR;  if an error occurs
while setting up the link (e.g. because \fIvarName\fR is the
name of array) then \fBTCL_ERROR\fR is returned and the interpreter's result
contains an error message.
.PP
.VS "TIP 312"
\fBTcl_LinkArray\fR is similar, but for arrays of fixed size (given by
the \fIsize\fR argument). When asked to allocate the backing C array
storage (via the \fBTCL_LINK_ALLOC\fR bit), it writes the address that
it allocated to the Tcl interpreter result in addition to storing the
location of the array in the C variable pointed to by \fIaddr\fR.
.VE "TIP 312"
.PP
The \fItype\fR argument specifies the type of the C variable,
or the type of the elements of the C array,
and must have one of the following values, optionally OR'ed with
\fBTCL_LINK_READ_ONLY\fR:
.TP
\fBTCL_LINK_INT\fR
.
The C variable, or each element of the C array, is of type \fBint\fR.
Any value written into the Tcl variable must have a proper integer
form acceptable to \fBTcl_GetIntFromObj\fR;  attempts to write
non-integer values into \fIvarName\fR will be rejected with
Tcl errors. Incomplete integer representations (like the empty
string, '+', '-' or the hex/octal/binary prefix) are accepted
as if they are valid too.
.TP
\fBTCL_LINK_UINT\fR
.
The C variable, or each element of the C array, is of type \fBunsigned int\fR.
Any value written into the Tcl variable must have a proper unsigned
integer form acceptable to \fBTcl_GetWideIntFromObj\fR and in the
platform's defined range for the \fBunsigned int\fR type; attempts to
write non-integer values (or values outside the range) into
\fIvarName\fR will be rejected with Tcl errors. Incomplete integer
representations (like the empty string, '+', '-' or the hex/octal/binary
prefix) are accepted as if they are valid too.
.TP
\fBTCL_LINK_CHAR\fR
.
The C variable, or each element of the C array, is of type \fBchar\fR.
Any value written into the Tcl variable must have a proper integer
form acceptable to \fBTcl_GetIntFromObj\fR and be in the range of the
\fBchar\fR datatype; attempts to write non-integer or out-of-range
values into \fIvarName\fR will be rejected with Tcl errors. Incomplete
integer representations (like the empty string, '+', '-' or the
hex/octal/binary prefix) are accepted as if they are valid too.
.RS
.PP
.VS "TIP 312"
If using an array of these, consider using \fBTCL_LINK_CHARS\fR instead.
.VE "TIP 312"
.RE
.TP
\fBTCL_LINK_CHARS\fR
.VS "TIP 312"
The C array is of type \fBchar *\fR and is mapped into Tcl as a string.
Any value written into the Tcl variable must have the same length as
the underlying storage. Only supported with \fBTcl_LinkArray\fR.
.VE "TIP 312"
.TP
\fBTCL_LINK_UCHAR\fR
.
The C variable, or each element of the C array, is of type \fBunsigned char\fR.
Any value written into the Tcl variable must have a proper unsigned
integer form acceptable to \fBTcl_GetIntFromObj\fR and in the
platform's defined range for the \fBunsigned char\fR type; attempts to
write non-integer values (or values outside the range) into
\fIvarName\fR will be rejected with Tcl errors. Incomplete integer
representations (like the empty string, '+', '-' or the hex/octal/binary
prefix) are accepted as if they are valid too.
.RS
.PP
.VS "TIP 312"
If using an array of these, consider using \fBTCL_LINK_BYTES\fR instead.
.VE "TIP 312"
.RE
.TP
\fBTCL_LINK_BYTES\fR
.VS "TIP 312"
The C array is of type \fBunsigned char *\fR and is mapped into Tcl
as a bytearray.
Any value written into the Tcl variable must have the same length as
the underlying storage. Only supported with \fBTcl_LinkArray\fR.
.VE "TIP 312"
.TP
\fBTCL_LINK_SHORT\fR
.
The C variable, or each element of the C array, is of type \fBshort\fR.
Any value written into the Tcl variable must have a proper integer
form acceptable to \fBTcl_GetIntFromObj\fR and be in the range of the
\fBshort\fR datatype; attempts to write non-integer or out-of-range
values into \fIvarName\fR will be rejected with Tcl errors. Incomplete
integer representations (like the empty string, '+', '-' or the
hex/octal/binary prefix) are accepted as if they are valid too.
.TP
\fBTCL_LINK_USHORT\fR
.
The C variable, or each element of the C array, is of type \fBunsigned short\fR.
Any value written into the Tcl variable must have a proper unsigned
integer form acceptable to \fBTcl_GetIntFromObj\fR and in the
platform's defined range for the \fBunsigned short\fR type; attempts to
write non-integer values (or values outside the range) into
\fIvarName\fR will be rejected with Tcl errors. Incomplete integer
representations (like the empty string, '+', '-' or the hex/octal/binary
prefix) are accepted as if they are valid too.
.TP
\fBTCL_LINK_LONG\fR
.
The C variable, or each element of the C array, is of type \fBlong\fR.
Any value written into the Tcl variable must have a proper integer
form acceptable to \fBTcl_GetLongFromObj\fR; attempts to write
non-integer or out-of-range
values into \fIvarName\fR will be rejected with Tcl errors. Incomplete
integer representations (like the empty string, '+', '-' or the
hex/octal/binary prefix) are accepted as if they are valid too.
.TP
\fBTCL_LINK_ULONG\fR
.
The C variable, or each element of the C array, is of type \fBunsigned long\fR.
Any value written into the Tcl variable must have a proper unsigned
integer form acceptable to \fBTcl_GetWideIntFromObj\fR and in the
platform's defined range for the \fBunsigned long\fR type; attempts to
write non-integer values (or values outside the range) into
\fIvarName\fR will be rejected with Tcl errors. Incomplete integer
representations (like the empty string, '+', '-' or the hex/octal/binary
prefix) are accepted as if they are valid too.
.TP
\fBTCL_LINK_DOUBLE\fR
.
The C variable, or each element of the C array, is of type \fBdouble\fR.
Any value written into the Tcl variable must have a proper real
form acceptable to \fBTcl_GetDoubleFromObj\fR;  attempts to write
non-real values into \fIvarName\fR will be rejected with
Tcl errors. Incomplete integer or real representations (like the
empty string, '.', '+', '-' or the hex/octal/binary prefix) are
accepted as if they are valid too.
.TP
\fBTCL_LINK_FLOAT\fR
.
The C variable, or each element of the C array, is of type \fBfloat\fR.
Any value written into the Tcl variable must have a proper real
form acceptable to \fBTcl_GetDoubleFromObj\fR and must be within the
range acceptable for a \fBfloat\fR; attempts to
write non-real values (or values outside the range) into
\fIvarName\fR will be rejected with Tcl errors. Incomplete integer
or real representations (like the empty string, '.', '+', '-' or
the hex/octal/binary prefix) are accepted as if they are valid too.
.TP
\fBTCL_LINK_WIDE_INT\fR
.
The C variable, or each element of the C array, is of type \fBTcl_WideInt\fR
(which is an integer type
at least 64-bits wide on all platforms that can support it.)
Any value written into the Tcl variable must have a proper integer
form acceptable to \fBTcl_GetWideIntFromObj\fR;  attempts to write
non-integer values into \fIvarName\fR will be rejected with
Tcl errors. Incomplete integer representations (like the empty
string, '+', '-' or the hex/octal/binary prefix) are accepted
as if they are valid too.
.TP
\fBTCL_LINK_WIDE_UINT\fR
.
The C variable, or each element of the C array, is of type \fBTcl_WideUInt\fR
(which is an unsigned integer type at least 64-bits wide on all platforms that
can support it.)
Any value written into the Tcl variable must have a proper unsigned
integer form acceptable to \fBTcl_GetWideIntFromObj\fR (it will be
cast to unsigned);
.\" FIXME! Use bignums instead.
attempts to write non-integer values into \fIvarName\fR will be
rejected with Tcl errors. Incomplete integer representations (like
the empty string, '+', '-' or the hex/octal/binary prefix) are accepted
as if they are valid too.
.TP
\fBTCL_LINK_BOOLEAN\fR
.
The C variable, or each element of the C array, is of type \fBint\fR.
If its value is zero then it will read from Tcl as
.QW 0 ;
otherwise it will read from Tcl as
.QW 1 .
Whenever \fIvarName\fR is
modified, the C variable will be set to a 0 or 1 value.
Any value written into the Tcl variable must have a proper boolean
form acceptable to \fBTcl_GetBooleanFromObj\fR;  attempts to write
non-boolean values into \fIvarName\fR will be rejected with
Tcl errors.
.TP
\fBTCL_LINK_STRING\fR
.
The C variable is of type \fBchar *\fR.
If its value is not NULL then it must be a pointer to a string
allocated with \fBTcl_Alloc\fR or \fBckalloc\fR.
Whenever the Tcl variable is modified the current C string will be
freed and new memory will be allocated to hold a copy of the variable's
new value.
If the C variable contains a NULL pointer then the Tcl variable
will read as
.QW NULL .
This is only supported by \fBTcl_LinkVar\fR.
.PP
If the \fBTCL_LINK_READ_ONLY\fR flag is present in \fItype\fR then the
variable will be read-only from Tcl, so that its value can only be
changed by modifying the C variable.
Attempts to write the variable from Tcl will be rejected with errors.
.PP
\fBTcl_UnlinkVar\fR removes the link previously set up for the

Changes to generic/tcl.decls.

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}
# Obsolete, use Tcl_FSJoinPath
declare 186 {
    char *Tcl_JoinPath(int argc, const char *const *argv,
	    Tcl_DString *resultPtr)
}
declare 187 {
    int Tcl_LinkVar(Tcl_Interp *interp, const char *varName, char *addr,
	    int type)
}

# This slot is reserved for use by the plus patch:
#  declare 188 {
#	Tcl_MainLoop
#  }






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}
# Obsolete, use Tcl_FSJoinPath
declare 186 {
    char *Tcl_JoinPath(int argc, const char *const *argv,
	    Tcl_DString *resultPtr)
}
declare 187 {
    int Tcl_LinkVar(Tcl_Interp *interp, const char *varName, void *addr,
	    int type)
}

# This slot is reserved for use by the plus patch:
#  declare 188 {
#	Tcl_MainLoop
#  }

Changes to generic/tclDecls.h.

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/* 185 */
EXTERN int		Tcl_IsSafe(Tcl_Interp *interp);
/* 186 */
EXTERN char *		Tcl_JoinPath(int argc, const char *const *argv,
				Tcl_DString *resultPtr);
/* 187 */
EXTERN int		Tcl_LinkVar(Tcl_Interp *interp, const char *varName,
				char *addr, int type);
/* Slot 188 is reserved */
/* 189 */
EXTERN Tcl_Channel	Tcl_MakeFileChannel(ClientData handle, int mode);
/* 190 */
EXTERN int		Tcl_MakeSafe(Tcl_Interp *interp);
/* 191 */
EXTERN Tcl_Channel	Tcl_MakeTcpClientChannel(ClientData tcpSocket);
................................................................................
    int (*tcl_Init) (Tcl_Interp *interp); /* 180 */
    void (*tcl_InitHashTable) (Tcl_HashTable *tablePtr, int keyType); /* 181 */
    int (*tcl_InputBlocked) (Tcl_Channel chan); /* 182 */
    int (*tcl_InputBuffered) (Tcl_Channel chan); /* 183 */
    int (*tcl_InterpDeleted) (Tcl_Interp *interp); /* 184 */
    int (*tcl_IsSafe) (Tcl_Interp *interp); /* 185 */
    char * (*tcl_JoinPath) (int argc, const char *const *argv, Tcl_DString *resultPtr); /* 186 */
    int (*tcl_LinkVar) (Tcl_Interp *interp, const char *varName, char *addr, int type); /* 187 */
    void (*reserved188)(void);
    Tcl_Channel (*tcl_MakeFileChannel) (ClientData handle, int mode); /* 189 */
    int (*tcl_MakeSafe) (Tcl_Interp *interp); /* 190 */
    Tcl_Channel (*tcl_MakeTcpClientChannel) (ClientData tcpSocket); /* 191 */
    char * (*tcl_Merge) (int argc, const char *const *argv); /* 192 */
    Tcl_HashEntry * (*tcl_NextHashEntry) (Tcl_HashSearch *searchPtr); /* 193 */
    void (*tcl_NotifyChannel) (Tcl_Channel channel, int mask); /* 194 */






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/* 185 */
EXTERN int		Tcl_IsSafe(Tcl_Interp *interp);
/* 186 */
EXTERN char *		Tcl_JoinPath(int argc, const char *const *argv,
				Tcl_DString *resultPtr);
/* 187 */
EXTERN int		Tcl_LinkVar(Tcl_Interp *interp, const char *varName,
				void *addr, int type);
/* Slot 188 is reserved */
/* 189 */
EXTERN Tcl_Channel	Tcl_MakeFileChannel(ClientData handle, int mode);
/* 190 */
EXTERN int		Tcl_MakeSafe(Tcl_Interp *interp);
/* 191 */
EXTERN Tcl_Channel	Tcl_MakeTcpClientChannel(ClientData tcpSocket);
................................................................................
    int (*tcl_Init) (Tcl_Interp *interp); /* 180 */
    void (*tcl_InitHashTable) (Tcl_HashTable *tablePtr, int keyType); /* 181 */
    int (*tcl_InputBlocked) (Tcl_Channel chan); /* 182 */
    int (*tcl_InputBuffered) (Tcl_Channel chan); /* 183 */
    int (*tcl_InterpDeleted) (Tcl_Interp *interp); /* 184 */
    int (*tcl_IsSafe) (Tcl_Interp *interp); /* 185 */
    char * (*tcl_JoinPath) (int argc, const char *const *argv, Tcl_DString *resultPtr); /* 186 */
    int (*tcl_LinkVar) (Tcl_Interp *interp, const char *varName, void *addr, int type); /* 187 */
    void (*reserved188)(void);
    Tcl_Channel (*tcl_MakeFileChannel) (ClientData handle, int mode); /* 189 */
    int (*tcl_MakeSafe) (Tcl_Interp *interp); /* 190 */
    Tcl_Channel (*tcl_MakeTcpClientChannel) (ClientData tcpSocket); /* 191 */
    char * (*tcl_Merge) (int argc, const char *const *argv); /* 192 */
    Tcl_HashEntry * (*tcl_NextHashEntry) (Tcl_HashSearch *searchPtr); /* 193 */
    void (*tcl_NotifyChannel) (Tcl_Channel channel, int mask); /* 194 */

Changes to generic/tclLink.c.

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typedef struct Link {
    Tcl_Interp *interp;		/* Interpreter containing Tcl variable. */
    Tcl_Obj *varName;		/* Name of variable (must be global). This is
				 * needed during trace callbacks, since the
				 * actual variable may be aliased at that time
				 * via upvar. */
    char *addr;			/* Location of C variable. */
    int bytes;			/* Size of C variable array. This is 0 when
				 * single variables, and >0 used for array
				 * variables. */
    int numElems;		/* Number of elements in C variable array.
				 * Zero for single variables. */
    int type;			/* Type of link (TCL_LINK_INT, etc.). */
    union {
................................................................................
 *----------------------------------------------------------------------
 */

int
Tcl_LinkVar(
    Tcl_Interp *interp,		/* Interpreter in which varName exists. */
    const char *varName,	/* Name of a global variable in interp. */
    char *addr,			/* Address of a C variable to be linked to
				 * varName. */
    int type)			/* Type of C variable: TCL_LINK_INT, etc. Also
				 * may have TCL_LINK_READ_ONLY OR'ed in. */
{
    Tcl_Obj *objPtr;
    Link *linkPtr;
    int code;






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typedef struct Link {
    Tcl_Interp *interp;		/* Interpreter containing Tcl variable. */
    Tcl_Obj *varName;		/* Name of variable (must be global). This is
				 * needed during trace callbacks, since the
				 * actual variable may be aliased at that time
				 * via upvar. */
    void *addr;			/* Location of C variable. */
    int bytes;			/* Size of C variable array. This is 0 when
				 * single variables, and >0 used for array
				 * variables. */
    int numElems;		/* Number of elements in C variable array.
				 * Zero for single variables. */
    int type;			/* Type of link (TCL_LINK_INT, etc.). */
    union {
................................................................................
 *----------------------------------------------------------------------
 */

int
Tcl_LinkVar(
    Tcl_Interp *interp,		/* Interpreter in which varName exists. */
    const char *varName,	/* Name of a global variable in interp. */
    void *addr,			/* Address of a C variable to be linked to
				 * varName. */
    int type)			/* Type of C variable: TCL_LINK_INT, etc. Also
				 * may have TCL_LINK_READ_ONLY OR'ed in. */
{
    Tcl_Obj *objPtr;
    Link *linkPtr;
    int code;