'\"
'\" Copyright (c) 1995-1996 Sun Microsystems, Inc.
'\"
'\" See the file "license.terms" for information on usage and redistribution
'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
'\" 
'\" SCCS: @(#) CrtSlave.3 1.13 96/03/25 20:00:42
'\" 
.so man.macros
.TH Tcl_CreateSlave 3 7.5 Tcl "Tcl Library Procedures"
.BS
.SH NAME
Tcl_IsSafe, Tcl_MakeSafe, Tcl_CreateSlave, Tcl_GetSlave, Tcl_GetSlaves, Tcl_GetMaster, Tcl_CreateAlias, Tcl_GetAlias, Tcl_GetAliases \- manage
multiple Tcl interpreters and aliases.
.SH SYNOPSIS
.nf
\fB#include <tcl.h>\fR
.sp
int
\fBTcl_IsSafe\fR(\fIinterp\fR)
.sp
int
\fBTcl_MakeSafe\fR(\fIinterp\fR)
.sp
Tcl_Interp *
\fBTcl_CreateSlave\fR(\fIinterp, slaveName, isSafe\fR)
.sp
Tcl_Interp *
\fBTcl_GetSlave\fR(\fIinterp, slaveName\fR)
.sp
Tcl_Interp *
\fBTcl_GetMaster\fR(\fIinterp\fR)
.sp
int
\fBTcl_GetInterpPath\fR(\fIaskingInterp, slaveInterp\fR)
.sp
int
\fBTcl_CreateAlias\fR(\fIslaveInterp, srcCmd, targetInterp, targetCmd, argc, argv\fR)
.sp
int
\fBTcl_GetAlias\fR(\fIinterp, srcCmd, targetInterpPtr, targetCmdPtr, argcPtr, argvPtr\fR)
.SH ARGUMENTS
.AS Tcl_InterpDeleteProc **delProcPtr
.AP Tcl_Interp *interp in
Interpreter in which to execute the specified command.
.AP char *slaveName in
Name of slave interpreter to create or manipulate.
.AP int isSafe in
Zero means the interpreter may have all Tcl functions. Non-zero means the
new interpreter's functionality should be limited to make it safe.
.AP Tcl_Interp *slaveInterp in
Interpreter to use for creating the source command for an alias (see
below).
.AP char *srcCmd in
Name of source command for alias.
.AP Tcl_Interp *targetInterp in
Interpreter that contains the target command for an alias.
.AP char *targetCmd in
Name of target command for alias in \fItargetInterp\fR.
.AP int argc in
Count of additional arguments to pass to the alias command.
.AP char **argv in
Vector of strings, the additional arguments to pass to the alias command.
This storage is owned by the caller.
.AP Tcl_Interp **targetInterpPtr in
Pointer to location to store the address of the interpreter where a target
command is defined for an alias.
.AP char **targetCmdPtr out
Pointer to location to store the address of the name of the target command
for an alias.
.AP int *argcPtr out
Pointer to location to store count of additional arguments to be passed to
the alias. The location is in storage owned by the caller.
.AP char ***argvPtr out
Pointer to location to store a vector of strings, the additional arguments
to pass to an alias. The location is in storage owned by the caller, the
vector of strings is owned by the called function.
.BE

.SH DESCRIPTION
.PP
These procedures are intended for access to the multiple interpreter
facility from inside C programs. They enable managing multiple interpreters
in a hierarchical relationship, and the management of aliases, commands
that when invoked in one interpreter execute a command in another
interpreter. The return value for those procedures that return an \fBint\fR
is either \fBTCL_OK\fR or \fBTCL_ERROR\fR. If \fBTCL_ERROR\fR is returned
then the \fBresult\fR field of the interpreter contains an error message.
.PP
\fBTcl_CreateSlave\fR creates a new interpreter as a slave of the given
interpreter. It also creates a slave command in the given interpreter which
allows the master interpreter to manipulate the slave. The slave
interpreter and the slave command have the specified name. If \fIisSafe\fR
is \fB1\fR, the new slave interpreter is made ``safe'' by removing all
unsafe functionality. If the creation failed, \fBNULL\fR is returned.
.PP
\fBTcl_IsSafe\fR returns \fB1\fR if the given interpreter is ``safe'',
\fB0\fR otherwise.
.PP
\fBTcl_MakeSafe\fR makes the given interpreter ``safe'' by removing all
non-core and core unsafe functionality. Note that if you call this after
adding some extension to an interpreter, all traces of that extension will
be removed from the interpreter. This operation always succeeds and returns
\fBTCL_OK\fR.
.PP
\fBTcl_GetSlave\fR returns a pointer to a slave interpreter of the given
interpreter. The slave interpreter is identified by the name specified.
If no such slave interpreter exists, \fBNULL\fR is returned.
.PP
\fBTcl_GetMaster\fR returns a pointer to the master interpreter of the
given interpreter. If the given interpreter has no master (it is a
top-level interpreter) then \fBNULL\fR is returned.
.PP
\fBTcl_GetInterpPath\fR sets the \fIresult\fR field in \fIaskingInterp\fR
to the relative path between \fIaskingInterp\fR and \fIslaveInterp\fR;
\fIslaveInterp\fR must be a slave of \fIaskingInterp\fR. If the computation
of the relative path succeeds, \fBTCL_OK\fR is returned, else
\fBTCL_ERROR\fR is returned and the \fIresult\fR field in
\fIaskingInterp\fR contains the error message.
.PP
\fBTcl_GetAlias\fR returns information about an alias of a specified name
in a given interpreter. Any of the result fields can be \fBNULL\fR, in
which case the corresponding datum is not returned. If a result field is
non\-\fBNULL\fR, the address indicated is set to the corresponding datum.
For example, if \fItargetNamePtr\fR is non\-\fBNULL\fR it is set to a
pointer to the string containing the name of the target command.
.PP
In order to map over all slave interpreters, use \fBTcl_Eval\fR with the
command \fBinterp slaves\fR and use the value (a Tcl list) deposited in the
\fBresult\fR field of the interpreter. Similarly, to map over all aliases
whose source commands are defined in an interpreter, use \fBTcl_Eval\fR
with the command \fBinterp aliases\fR and use the value (a Tcl list)
deposited in the \fBresult\fR field. Note that the storage of this list
belongs to Tcl, so you should copy it before invoking any other Tcl
commands in that interpreter.
.SH "SEE ALSO"
For a description of the Tcl interface to multiple interpreters, see
\fIinterp(n)\fR.

.SH KEYWORDS
alias, command, interpreter, master, slave