view doc/glibc-functions/explicit_bzero.texi @ 19639:41bd1e8f88b2

doc: Add info about Android 9.0. * doc/**/*.texi: Add info about functions and headers in Bionic from Android 9.0.
author Bruno Haible <bruno@clisp.org>
date Thu, 10 May 2018 18:16:59 +0200
parents f1a31809efb2
children d4661c7ea0d0
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@node explicit_bzero
@subsection @code{explicit_bzero}
@findex explicit_bzero

Gnulib module: explicit_bzero

The @code{explicit_bzero} function is an approximation to what is
needed, and does not suffice in general to erase information.
Although calling @code{explicit_bzero} should clear the memory in
question, the information that was in memory may still be available
elsewhere on the machine.  Proper implementation of information
erasure requires support from levels below C code.

Portability problems fixed by Gnulib:
@itemize
@item
This function is missing on some platforms:
glibc 2.24, FreeBSD 10, NetBSD 7.1, OpenBSD 5.4, macOS 10.12, Solaris 11.3, Android 9.0,
and many other systems.
@end itemize

Portability problems not fixed by Gnulib:
@itemize
@item
Although the module's implementation should clear the memory on
platforms compatible with GCC and on platforms using traditional
linkers, it may not clear the memory on non-GCC platforms that use
whole-program optimization.
@end itemize