Tcl_SetAssocData(3)					      Tcl Library Procedures					       Tcl_SetAssocData(3)

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NAME

       Tcl_GetAssocData, Tcl_SetAssocData, Tcl_DeleteAssocData - manage associations of string keys and user specified data with Tcl interpreters

SYNOPSIS

       #include <tcl.h>

       ClientData
       Tcl_GetAssocData(interp, key, delProcPtr)

       Tcl_SetAssocData(interp, key, delProc, clientData)

       Tcl_DeleteAssocData(interp, key)

ARGUMENTS

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

       const char *key (in)			       Key  for  association  with  which  to store data or from which to delete or retrieve data.
						       Typically the module prefix for a package.

       Tcl_InterpDeleteProc *delProc (in)	       Procedure to call when interp is deleted.

       Tcl_InterpDeleteProc **delProcPtr (in)	       Pointer to location in which to store address of current deletion  procedure  for  associa-
						       tion.  Ignored if NULL.

       ClientData clientData (in)		       Arbitrary  one-word  value associated with the given key in this interpreter.  This data is
						       owned by the caller.
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DESCRIPTION

       These procedures allow extensions to associate their own data with a Tcl interpreter.  An association consists of a string  key,  typically
       the  name  of the extension, and a one-word value, which is typically a pointer to a data structure holding data specific to the extension.
       Tcl makes no interpretation of either the key or the value for an association.

       Storage management is facilitated by storing with each association a procedure to call when the interpreter is deleted. This procedure  can
       dispose of the storage occupied by the client's data in any way it sees fit.

       Tcl_SetAssocData  creates  an association between a string key and a user specified datum in the given interpreter.  If there is already an
       association with the given key, Tcl_SetAssocData overwrites it with the new information.  It is up to callers  to  organize  their  use	of
       names to avoid conflicts, for example, by using package names as the keys.  If the deleteProc argument is non-NULL it specifies the address
       of a procedure to invoke if the interpreter is deleted before the association is deleted.  DeleteProc should have arguments and result that
       match the type Tcl_InterpDeleteProc:
	      typedef void Tcl_InterpDeleteProc(
		      ClientData clientData,
		      Tcl_Interp *interp);
       When  deleteProc is invoked the clientData and interp arguments will be the same as the corresponding arguments passed to Tcl_SetAssocData.
       The deletion procedure will not be invoked if the association is deleted before the interpreter is deleted.

       Tcl_GetAssocData returns the datum stored in the association with the specified key in the given interpreter, and if the  delProcPtr  field
       is  non-NULL, the address indicated by it gets the address of the delete procedure stored with this association. If no association with the
       specified key exists in the given interpreter Tcl_GetAssocData returns NULL.

       Tcl_DeleteAssocData deletes an association with a specified key in the given interpreter.  Then it calls the deletion procedure.

KEYWORDS

       association, data, deletion procedure, interpreter, key

Tcl									7.5						       Tcl_SetAssocData(3)