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man pages section 3: Extended Library Functions, Volume 1

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Updated: Wednesday, July 27, 2022
 
 

Tcl_Alloc (3tcl)

Name

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

Synopsis

#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)

Description

Tcl_Alloc(3tcl)             Tcl Library Procedures             Tcl_Alloc(3tcl)



______________________________________________________________________________

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

SYNOPSIS
       #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)

ARGUMENTS
       unsigned 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 allo-
       cation.

       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  syn-
       onyms  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.


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



ATTRIBUTES
       See attributes(7) for descriptions of the following attributes:


       +---------------+------------------+
       |ATTRIBUTE TYPE | ATTRIBUTE VALUE  |
       +---------------+------------------+
       |Availability   | runtime/tcl-8    |
       +---------------+------------------+
       |Stability      | Uncommitted      |
       +---------------+------------------+

NOTES
       Source  code  for open source software components in Oracle Solaris can
       be found at https://www.oracle.com/downloads/opensource/solaris-source-
       code-downloads.html.

       This     software     was    built    from    source    available    at
       https://github.com/oracle/solaris-userland.   The  original   community
       source was downloaded from  http://prdownloads.sourceforge.net/tcl/tcl-
       core8.6.7-src.tar.gz.

       Further information about this software can be found on the open source
       community website at https://www.tcl.tk/.



Tcl                                   7.5                      Tcl_Alloc(3tcl)