src/lib/libc/sys/brk.2, branch stable/13

Remove $FreeBSD$: one-line nroff pattern

2023-08-23T17:43:32+00:00

Remove /^\.\\"\s*\$FreeBSD\$$\n/

Similar commit in main:
(cherry picked from commit b2c76c41be32)

Reimplement brk() and sbrk() to avoid the use of _end.

2018-06-04T19:35:15+00:00

Previously, libc.so would initialize its notion of the break address
using _end, a special symbol emitted by the static linker following
the bss section.  Compatibility issues between lld and ld.bfd could
cause the wrong definition of _end (libc.so's definition rather than
that of the executable) to be used, breaking the brk()/sbrk()
interface.

Avoid this problem and future interoperability issues by simply not
relying on _end.  Instead, modify the break() system call to return
the kernel's view of the current break address, and have libc
initialize its state using an extra syscall upon the first use of the
interface.  As a side effect, this appears to fix brk()/sbrk() usage
in executables run with rtld direct exec, since the kernel and libc.so
no longer maintain separate views of the process' break address.

PR:		228574
Reviewed by:	kib (previous version)
MFC after:	2 months
Differential Revision:	https://reviews.freebsd.org/D15663

Indicate the brk/sbrk are deprecated and not portable.

2018-05-24T18:32:54+00:00

More firmly suggest mmap(2) instead.

Include the history of arm64 and riscv shipping without brk/sbrk.

Mention that sbrk(0) produces unreliable results.

Reviewed by:	emaste, Marcin Cieślak
MFC after:	3 days
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D15535

Renumber copyright clause 4

2017-02-28T23:42:47+00:00

Renumber cluase 4 to 3, per what everybody else did when BSD granted
them permission to remove clause 3. My insistance on keeping the same
numbering for legal reasons is too pedantic, so give up on that point.

Submitted by:	Jan Schaumann 
Pull Request:	https://github.com/freebsd/freebsd/pull/96

Remove sys/types.h due to STANDARDS and unistd.h also includes sys/types.h.

2015-12-15T15:19:06+00:00

Per Regents of the University of Calfornia letter, remove advertising

2007-01-09T00:28:16+00:00

clause.

# If I've done so improperly on a file, please let me know.

Sort sections.

2005-01-20T09:17:07+00:00

mdoc(7) police: Tidy up the syscall language.

2002-12-18T09:22:32+00:00

Stop calling system calls "function calls".

Use "The .Fn system call" a-la "The .Nm utility".

When referring to a non-BSD implementation in
the HISTORY section, call syscall a function,
to be safe.

Change brk's prototype from char brk(const char ) to int brk(const void *)

2002-01-24T12:11:31+00:00

and sbrk's prototype from char *sbrk(int) to void *sbrk(intptr_t).

This makes us more consistant with NetBSD and standards which include
these functions. Bruce pointed out that ptrdiff_t would probably
have been better than intptr_t, but this doesn't match other
implimentations.

Also remove local declarations of sbrk and unnecessary casting.

PR:		32296
Tested by:	Harti Brandt 
MFC after:	1 month

mdoc(7) police: Use the new .In macro for #include statements.

2001-10-01T16:09:29+00:00