Provided by: tcl8.5-doc_8.5.11-1ubuntu1_all bug

NAME

       Tcl_IsSafe, Tcl_MakeSafe, Tcl_CreateSlave, Tcl_GetSlave, Tcl_GetMaster, Tcl_GetInterpPath,
       Tcl_CreateAlias,  Tcl_CreateAliasObj,  Tcl_GetAlias,  Tcl_GetAliasObj,  Tcl_ExposeCommand,
       Tcl_HideCommand - manage multiple Tcl interpreters, aliases and hidden commands

SYNOPSIS

       #include <tcl.h>

       int
       Tcl_IsSafe(interp)

       int
       Tcl_MakeSafe(interp)

       Tcl_Interp *
       Tcl_CreateSlave(interp, slaveName, isSafe)

       Tcl_Interp *
       Tcl_GetSlave(interp, slaveName)

       Tcl_Interp *
       Tcl_GetMaster(interp)

       int
       Tcl_GetInterpPath(askingInterp, slaveInterp)

       int
       Tcl_CreateAlias(slaveInterp, slaveCmd, targetInterp, targetCmd,
                       argc, argv)

       int
       Tcl_CreateAliasObj(slaveInterp, slaveCmd, targetInterp, targetCmd,
                          objc, objv)

       int
       Tcl_GetAlias(interp, slaveCmd, targetInterpPtr, targetCmdPtr,
                    argcPtr, argvPtr)

       int
       Tcl_GetAliasObj(interp, slaveCmd, targetInterpPtr, targetCmdPtr,
                       objcPtr, objvPtr)

       int
       Tcl_ExposeCommand(interp, hiddenCmdName, cmdName)

       int
       Tcl_HideCommand(interp, cmdName, hiddenCmdName)

ARGUMENTS

       Tcl_Interp *interp (in)                           Interpreter  in  which  to  execute  the
                                                         specified command.

       const char *slaveName (in)                        Name of slave interpreter to  create  or
                                                         manipulate.

       int isSafe (in)                                   If  non-zero,  a  “safe”  slave  that is
                                                         suitable for running untrusted  code  is
                                                         created,  otherwise  a  trusted slave is
                                                         created.

       Tcl_Interp *slaveInterp (in)                      Interpreter  to  use  for  creating  the
                                                         source command for an alias (see below).

       const char *slaveCmd (in)                         Name of source command for alias.

       Tcl_Interp *targetInterp (in)                     Interpreter  that  contains  the  target
                                                         command for an alias.

       const char *targetCmd (in)                        Name of  target  command  for  alias  in
                                                         targetInterp.

       int argc (in)                                     Count of additional arguments to pass to
                                                         the alias command.

       const char *const *argv (in)                      Vector  of   strings,   the   additional
                                                         arguments  to pass to the alias command.
                                                         This storage is owned by the caller.

       int objc (in)                                     Count of additional object arguments  to
                                                         pass to the alias object command.

       Tcl_Obj **objv (in)                               Vector   of   Tcl_Obj   structures,  the
                                                         additional object arguments to  pass  to
                                                         the  alias object command.  This storage
                                                         is owned by the caller.

       Tcl_Interp **targetInterpPtr (in)                 Pointer to location to store the address
                                                         of   the   interpreter  where  a  target
                                                         command is defined for an alias.

       const char **targetCmdPtr (out)                   Pointer to location to store the address
                                                         of the name of the target command for an
                                                         alias.

       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.

       const 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.

       int *objcPtr (out)                                Pointer to location to  store  count  of
                                                         additional object arguments to be passed
                                                         to the alias. The location is in storage
                                                         owned by the caller.

       Tcl_Obj ***objvPtr (out)                          Pointer to location to store a vector of
                                                         Tcl_Obj   structures,   the   additional
                                                         arguments  to  pass  to  an object alias
                                                         command.  The  location  is  in  storage
                                                         owned  by  the  caller,  the  vector  of
                                                         Tcl_Obj  structures  is  owned  by   the
                                                         called function.

       const char *cmdName (in)                          Name  of  an  exposed command to hide or
                                                         create.

       const char *hiddenCmdName (in)                    Name under which  a  hidden  command  is
                                                         stored  and with which it can be exposed
                                                         or invoked.
_________________________________________________________________

DESCRIPTION

       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 int is either
       TCL_OK or TCL_ERROR. If TCL_ERROR is returned then the result  field  of  the  interpreter
       contains an error message.

       Tcl_CreateSlave  creates  a new interpreter as a slave of interp.  It also creates a slave
       command named slaveName in interp which allows interp to manipulate  the  new  slave.   If
       isSafe  is  zero,  the command creates a trusted slave in which Tcl code has access to all
       the Tcl commands.  If it is 1, the command creates a “safe” slave in which  Tcl  code  has
       access only to set of Tcl commands defined as “Safe Tcl”; see the manual entry for the Tcl
       interp command for details.  If the creation of the new slave interpreter failed, NULL  is
       returned.

       Tcl_IsSafe  returns  1 if interp is “safe” (was created with the TCL_SAFE_INTERPRETER flag
       specified), 0 otherwise.

       Tcl_MakeSafe marks interp as “safe”, so that future calls to Tcl_IsSafe will return 1.  It
       also removes all known potentially-unsafe core functionality (both commands and variables)
       from interp.  However, it cannot know what parts of an extension or application  are  safe
       and  does  not  make  any attempt to remove those parts, so safety is not guaranteed after
       calling Tcl_MakeSafe.  Callers will want to take care with their use  of  Tcl_MakeSafe  to
       avoid  false  claims  of  safety.   For  many  situations, Tcl_CreateSlave may be a better
       choice, since it creates interpreters in a known-safe state.

       Tcl_GetSlave returns a pointer to a slave interpreter of interp. The slave interpreter  is
       identified by slaveName.  If no such slave interpreter exists, NULL is returned.

       Tcl_GetMaster  returns  a  pointer  to  the master interpreter of interp. If interp has no
       master (it is a top-level interpreter) then NULL is returned.

       Tcl_GetInterpPath sets the result field in  askingInterp  to  the  relative  path  between
       askingInterp  and  slaveInterp;  slaveInterp  must  be  a  slave  of  askingInterp. If the
       computation of the relative path succeeds, TCL_OK is returned, else TCL_ERROR is  returned
       and the result field in askingInterp contains the error message.

       Tcl_CreateAlias creates an object command named slaveCmd in slaveInterp that when invoked,
       will cause the command targetCmd to be invoked in targetInterp. The arguments specified by
       the  strings  contained  in  argv  are  always  prepended to any arguments supplied in the
       invocation of slaveCmd and passed to targetCmd.   This  operation  returns  TCL_OK  if  it
       succeeds,  or  TCL_ERROR if it fails; in that case, an error message is left in the object
       result of slaveInterp.  Note that there are no restrictions on the  ancestry  relationship
       (as created by Tcl_CreateSlave) between slaveInterp and targetInterp. Any two interpreters
       can be used, without any restrictions on how they are related.

       Tcl_CreateAliasObj is similar to Tcl_CreateAlias except that it takes a vector of  objects
       to pass as additional arguments instead of a vector of strings.

       Tcl_GetAlias  returns  information  about  an alias aliasName in interp. Any of the result
       fields can be NULL, in which case the corresponding datum is not  returned.  If  a  result
       field  is non-NULL, the address indicated is set to the corresponding datum.  For example,
       if targetNamePtr is non-NULL it is set to a pointer to the string containing the  name  of
       the target command.

       Tcl_GetAliasObj is similar to Tcl_GetAlias except that it returns a pointer to a vector of
       Tcl_Obj structures instead of a vector of strings.

       Tcl_ExposeCommand moves the command named hiddenCmdName from the set of hidden commands to
       the set of exposed commands, putting it under the name cmdName.  HiddenCmdName must be the
       name of an existing hidden command, or the operation will return TCL_ERROR  and  leave  an
       error  message in the result field in interp.  If an exposed command named cmdName already
       exists, the operation returns TCL_ERROR and leaves an error message in the  object  result
       of  interp.   If the operation succeeds, it returns TCL_OK.  After executing this command,
       attempts to use cmdName in a call to Tcl_Eval or with the  Tcl  eval  command  will  again
       succeed.

       Tcl_HideCommand  moves  the  command named cmdName from the set of exposed commands to the
       set of hidden commands, under the name hiddenCmdName.  CmdName must  be  the  name  of  an
       existing  exposed  command,  or  the  operation  will  return TCL_ERROR and leave an error
       message in the object result of interp.  Currently both cmdName and hiddenCmdName must not
       contain  namespace  qualifiers,  or the operation will return TCL_ERROR and leave an error
       message in the object result of interp.  The CmdName will  be  looked  up  in  the  global
       namespace, and not relative to the current namespace, even if the current namespace is not
       the global one.  If a hidden command whose  name  is  hiddenCmdName  already  exists,  the
       operation also returns TCL_ERROR and the result field in interp contains an error message.
       If the operation succeeds, it returns TCL_OK.  After executing this command,  attempts  to
       use cmdName in a call to Tcl_Eval or with the Tcl eval command will fail.

       For a description of the Tcl interface to multiple interpreters, see interp(3tcl).

SEE ALSO

       interp

KEYWORDS

       alias, command, exposed commands, hidden commands, interpreter, invoke, master, slave