Tcl Library Procedures - Tcl_Alloc manual page

### NAME

Tcl_Alloc, Tcl_Free, Tcl_Realloc, Tcl_AttemptAlloc, Tcl_AttemptRealloc - allocate or free heap memory

### SYNOPSIS

#include <tcl.h>
char *
Tcl_Alloc(size)
Tcl_Free(ptr)
char *
Tcl_Realloc(ptr, size)
char *
Tcl_AttemptAlloc(size)
char *
Tcl_AttemptRealloc(ptr, size)

### ARGUMENTS

int size (in)
  Size in bytes of the memory block to allocate.

char *ptr (in)
  Pointer to memory block to free or realloc.

### DESCRIPTION

These procedures provide a platform and compiler independent interface for memory allocation. Programs that need to transfer ownership of memory blocks between Tcl and other modules should use these routines rather than the native malloc() and free() routines provided by the C run-time library.

Tcl_Alloc returns a pointer to a block of at least size bytes suitably aligned for any use.

Tcl_Free makes the space referred to by ptr available for further allocation.

Tcl_Realloc changes the size of the block pointed to by ptr to size bytes and returns a pointer to the new block. The contents will be unchanged up to the lesser of the new and old sizes. The returned location may be different from ptr.

Tcl_AttemptAlloc and Tcl_AttemptRealloc are identical in function to Tcl_Alloc and Tcl_Realloc, except that Tcl_AttemptAlloc and Tcl_AttemptRealloc will not cause the Tcl interpreter to panic if the memory allocation fails. If the allocation fails, these functions will return NULL.

### KEYWORDS

alloc, allocation, free, malloc, memory, realloc

    Copyright © 1995-1996 Sun Microsystems, Inc.
    Copyright © 1995-1997 Roger E. Critchlow Jr.