getdate.3: Use blank definition of _GNU_SOURCE

Only the definedness of _GNU_SOURCE matters, so eliminate a possible
source of confusion by not using a specific replacement text in the
example program.

Signed-off-by: Rasmus Villemoes <rv@rasmusvillemoes.dk>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
open_by_handle_at.2: Add reference to feature_test_macros(7)

Signed-off-by: Rasmus Villemoes <rv@rasmusvillemoes.dk>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
recvmmsg.2: Add reference to feature_test_macros(7)

Signed-off-by: Rasmus Villemoes <rv@rasmusvillemoes.dk>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
sendmmsg.2: Add reference to feature_test_macros(7)

Signed-off-by: Rasmus Villemoes <rv@rasmusvillemoes.dk>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
malloc_get_state.3: SYNOPSIS: use correct header

The nonstandard functions malloc_set_state() and
malloc_get_state() are provided by <malloc.h> not <stdlib.h>.

Signed-off-by: Rasmus Villemoes <rv@rasmusvillemoes.dk>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
locale.7: Add some SEE ALSO references

Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
locale.1: Add FILES section, add charmap(5) reference

Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
locale.5: Clarify AM/PM settings a bit

localedef(1) complains if really undefined, should be empty instead.
Also: add some SEE ALSO references.

Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
posix_fallocate.3: ATTRIBUTES: Note function that is thread-safe

The function posix_fallocate() is thread safe.

Signed-off-by: Peng Haitao <penght@cn.fujitsu.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
posix_openpt.3: ATTRIBUTES: Note function that is thread-safe

The function posix_openpt() is thread safe.

Signed-off-by: Peng Haitao <penght@cn.fujitsu.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
mq_open.3: ATTRIBUTES: Note function that is thread-safe

The function mq_open() is thread safe.

Signed-off-by: Peng Haitao <penght@cn.fujitsu.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
mq_receive.3: ATTRIBUTES: Note functions that are thread-safe

The functions mq_receive() and mq_timedreceive() are thread safe.

Signed-off-by: Peng Haitao <penght@cn.fujitsu.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
mq_send.3: ATTRIBUTES: Note functions that are thread-safe

The functions mq_send() and mq_timedsend() are thread safe.

Signed-off-by: Peng Haitao <penght@cn.fujitsu.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>