Tcl Library Procedures                            TclAlloc(3TCL)





NAME
     TclAlloc,    TclFree,    TclRealloc,    TclAttemptAlloc,
     TclAttemptRealloc, ckalloc, ckfree, ckrealloc, attemptckal-
     loc, attemptckrealloc - allocate or free heap memory

SYNOPSIS
     #include 

     char *
     TclAlloc(size)

     void
     TclFree(ptr)

     char *
     TclRealloc(ptr, size)

     char *
     TclAttemptAlloc(size)

     char *
     TclAttemptRealloc(ptr, size)

     char *
     ckalloc(size)

     void
     ckfree(ptr)

     char *
     ckrealloc(ptr, size)

     char *
     attemptckalloc(size)

     char *
     attemptckrealloc(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



Tcl                     Last change: 7.5                        1






Tcl Library Procedures                            TclAlloc(3TCL)



     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.

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

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

     TclRealloc 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.

     TclAttemptAlloc and  TclAttemptRealloc  are  identical  in
     function   to   TclAlloc   and   TclRealloc,  except  that
     TclAttemptAlloc and TclAttemptRealloc will not  cause  the
     Tcl interpreter to panic if the memory allocation fails.  If
     the allocation fails,  these  functions  will  return  NUL.
     Note  that on some platforms, attempting to allocate a block
     of memory will also cause these functions to return NUL.

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


KEYWORDS
     alloc,   allocation,   free,   malloc,   memory,    realloc,
     TCLMEMDEBUG

ATRIBUTES
     See attributes(5) for descriptions of the  following  attri-
     butes:













Tcl                     Last change: 7.5                        2






Tcl Library Procedures                            TclAlloc(3TCL)



     
       ATRIBUTE TYPE     ATRIBUTE VALUE
    
     Availability         SUNWTcl        
    
     Interface Stability  Uncommitted    
    

NOTES
     Source for Tcl is available on http:/opensolaris.org.













































Tcl                     Last change: 7.5                        3