Tcl_SetRecursionLimit manual page - Tcl Library Procedures

## Tcl8.5.15/Tk8.5.15 Documentation > TclLib > SetRecLmt

### Tcl/Tk Applications | Tcl Commands | Tk Commands | Tcl Library | Tk Library

### NAME

Tcl_SetRecursionLimit - set maximum allowable nesting depth in interpreter

### SYNOPSIS

#include <tcl8.5/tcl.h>
int
Tcl_SetRecursionLimit(interp, depth)

### ARGUMENTS

Tcl_Interp *interp (in)
  Interpreter whose recursion limit is to be set. Must be greater than zero.

int depth (in)
  New limit for nested calls to Tcl_Eval for interp.

### DESCRIPTION

At any given time Tcl enforces a limit on the number of recursive calls that may be active for Tcl_Eval and related procedures such as Tcl_GlobalEval. Any call to Tcl_Eval that exceeds this depth is aborted with an error. By default the recursion limit is 1000.

Tcl_SetRecursionLimit may be used to change the maximum allowable nesting depth for an interpreter. The depth argument specifies a new limit for interp, and Tcl_SetRecursionLimit returns the old limit. To read out the old limit without modifying it, invoke Tcl_SetRecursionLimit with depth equal to 0.

The Tcl_SetRecursionLimit only sets the size of the Tcl call stack: it cannot by itself prevent stack overflows on the C stack being used by the application. If your machine has a limit on the size of the C stack, you may get stack overflows before reaching the limit set by Tcl_SetRecursionLimit. If this happens, see if there is a mechanism in your system for increasing the maximum size of the C stack.

### KEYWORDS

nesting depth, recursion
Copyright © 1995-1997 Roger E. Critchlow Jr. Copyright © 1989-1993 The Regents of the University of California. Copyright © 1994-1996 Sun Microsystems, Inc.