DOKK / manpages / debian 10 / tcl8.6-doc / ckrealloc.3tcl.en
Tcl_Alloc(3tcl) Tcl Library Procedures Tcl_Alloc(3tcl) 







Tcl_Alloc, Tcl_Free, Tcl_Realloc, Tcl_AttemptAlloc,
    Tcl_AttemptRealloc, ckalloc, ckfree, ckrealloc, attemptckalloc,
    attemptckrealloc - allocate or free heap memory








#include <tcl.h>

char *
Tcl_Alloc(size)

void
Tcl_Free(ptr)

char *
Tcl_Realloc(ptr, size)

char *
Tcl_AttemptAlloc(size)

char *
Tcl_AttemptRealloc(ptr, size)

char *
ckalloc(size)

void
ckfree(ptr)

char *
ckrealloc(ptr, size)

char *
attemptckalloc(size)

char *
attemptckrealloc(ptr, size)









  
unsigned int size (in)

  
Size in bytes of the memory block to allocate.

  
char *ptr (in)

  
Pointer to memory block to free or realloc.
    
    

    

  










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. If ptr is NULL,
    this is equivalent to calling Tcl_Alloc with just the size
    argument.


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. Note that on some
    platforms, but not all, attempting to allocate a zero-sized block of memory
    will also cause these functions to return NULL.


The procedures ckalloc, ckfree, ckrealloc,
    attemptckalloc, and attemptckrealloc are implemented as
    macros. Normally, they are synonyms for the corresponding procedures
    documented on this page. When Tcl and all modules calling Tcl are compiled
    with TCL_MEM_DEBUG defined, however, these macros are redefined to be
    special debugging versions of these procedures. To support Tcl's memory
    debugging within a module, use the macros rather than direct calls to
    Tcl_Alloc, etc.










alloc, allocation, free, malloc, memory, realloc,
  TCL_MEM_DEBUG







  

    7.5
    Tcl