Issue in man page malloc.3

Issue in man page malloc.3

[Helge Kreutzmann]

Without further ado, the following was found:

Issue:    preserve errno → preserve I<errno>

"If your program uses a private memory allocator, it should do so by "
"replacing B<malloc>(), B<free>(), B<calloc>(), and B<realloc>().  The "
"replacement functions must implement the documented glibc behaviors, "
"including I<errno> handling, size-zero allocations, and overflow checking; "
"otherwise, other library routines may crash or operate incorrectly.  For "
"example, if the replacement I<free>()  does not preserve errno, then "
"seemingly unrelated library routines may fail without having a valid reason "
"in I<errno>.  Private memory allocators may also need to replace other glibc "
"functions; see \"Replacing malloc\" in the glibc manual for details."

Re: Issue in man page malloc.3

[Alejandro Colomar]

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On 12/4/22 10:07, Helge Kreutzmann wrote:
> Without further ado, the following was found:
> 
> Issue:    preserve errno → preserve I<errno>
> 
> "If your program uses a private memory allocator, it should do so by"
> "replacing B<malloc>(), B<free>(), B<calloc>(), and B<realloc>().  The"
> "replacement functions must implement the documented glibc behaviors,"
> "including I<errno> handling, size-zero allocations, and overflow checking;"
> "otherwise, other library routines may crash or operate incorrectly.  For"
> "example, if the replacement I<free>()  does not preserve errno, then"
> "seemingly unrelated library routines may fail without having a valid reason"
> "in I<errno>.  Private memory allocators may also need to replace other glibc"
> "functions; see \"Replacing malloc\" in the glibc manual for details."

Fixed.  Thanks.

-- 
<http://www.alejandro-colomar.es/>

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Issue in man page malloc.3

[Helge Kreutzmann]

Without further ado, the following was found:

Issue:    enough that → enough, so that

"The behavior of I<realloc(p,\\ 0)> in glibc doesn't conform to any of C99, "
"C11, POSIX.1-2001, POSIX.1-2004, POSIX.1-2008, POSIX.1-2013, POSIX.1-2017, "
"or POSIX.1-2024.  The C17 specification was changed to make it conforming, "
"but that specification made it impossible to write code that reliably "
"determines if the input pointer is freed after I<realloc(p,\\ 0)>, and C23 "
"changed it again to make this undefined behavior, acknowledging that the C17 "
"specification was broad enough that undefined behavior wasn't worse than "
"that."

Re: Issue in man page malloc.3

[Alejandro Colomar]

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Hi Helge,

On Sun, Aug 24, 2025 at 02:48:43PM +0000, Helge Kreutzmann wrote:
> Without further ado, the following was found:
> 
> Issue:    enough that → enough, so that

Thanks; I've applied your suggestion.
<https://www.alejandro-colomar.es/src/alx/linux/man-pages/man-pages.git/commit/?h=contrib&id=5765b190cc2e6fba6c12fdf4174aab6734cb2a72>
(at port 80.)


Cheers,
Alex

> 
> "The behavior of I<realloc(p,\\ 0)> in glibc doesn't conform to any of C99, "
> "C11, POSIX.1-2001, POSIX.1-2004, POSIX.1-2008, POSIX.1-2013, POSIX.1-2017, "
> "or POSIX.1-2024.  The C17 specification was changed to make it conforming, "
> "but that specification made it impossible to write code that reliably "
> "determines if the input pointer is freed after I<realloc(p,\\ 0)>, and C23 "
> "changed it again to make this undefined behavior, acknowledging that the C17 "
> "specification was broad enough that undefined behavior wasn't worse than "
> "that."
> 

-- 
<https://www.alejandro-colomar.es>
Use port 80 (that is, <...:80/>).

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