build-sys: expect C99 compliant compiler

Expectation to support older standards is not justified.

Signed-off-by: Sami Kerola <kerolasa@iki.fi>
include: fix spurious list.h warnings

include/list.h:224:17: warning: ISO C forbids omitting the middle term of a ?: expression [-pedantic]
include/list.h:255:19: warning: ISO C forbids omitting the middle term of a ?: expression [-pedantic]

Compilation warned about that at least 110 times.

Signed-off-by: Sami Kerola <kerolasa@iki.fi>
build: fix redundant redeclaration warnings

env.c:24:15: warning: redundant redeclaration of 'environ' [-Wredundant-decls]
su.c:81:15: warning: redundant redeclaration of 'environ' [-Wredundant-decls]

fstab.c:581:14: warning: redundant redeclaration of 'strsignal' [-Wredundant-decls]

kill.h:1:13: note: previous declaration of 'get_pids' was here
kill.c:152:13: warning: redundant redeclaration of 'get_pids' [-Wredundant-decls]

kill.c:142:5: warning: redundant redeclaration of 'main' [-Wredundant-decls]
getopt.c:89:5: warning: redundant redeclaration of 'main' [-Wredundant-decls]

agetty.c:536:15: warning: redundant redeclaration of 'optarg' [-Wredundant-decls]
agetty.c:537:13: warning: redundant redeclaration of 'optind' [-Wredundant-decls]
script.c:161:13: warning: redundant redeclaration of 'optind' [-Wredundant-decls]
wall.c:96:13: warning: redundant redeclaration of 'optind' [-Wredundant-decls]

libmount.h:362:26: note: previous declaration of 'mnt_update_get_fs' was here
libmount.h:454:26: note: previous declaration of 'mnt_context_get_fs' was here
mountP.h:383:26: warning: redundant redeclaration of 'mnt_context_get_fs' [-Wredundant-decls]
mountP.h:398:26: warning: redundant redeclaration of 'mnt_update_get_fs' [-Wredundant-decls]

Signed-off-by: Sami Kerola <kerolasa@iki.fi>
build: fix unused parameter warnings

pager.c:203:14: warning: unused parameter 'argc' [-Wunused-parameter]
pager.c:203:26: warning: unused parameter 'argv' [-Wunused-parameter]

randutils.c:108:14: warning: unused parameter 'argc' [-Wunused-parameter]
randutils.c:108:26: warning: unused parameter 'argv' [-Wunused-parameter]

optstr.c:774:37: warning: unused parameter 'optstr' [-Wunused-parameter]
optstr.c:774:51: warning: unused parameter 'value' [-Wunused-parameter]
optstr.c:774:65: warning: unused parameter 'valsz' [-Wunused-parameter]
optstr.c:774:79: warning: unused parameter 'next' [-Wunused-parameter]

Signed-off-by: Sami Kerola <kerolasa@iki.fi>
sysfs: fix printf format warnings

sysfs.c:93:3: warning: format '%u' expects argument of type 'unsigned
	int *', but argument 3 has type 'int *' [-Wformat]
sysfs.c:93:3: warning: format '%u' expects argument of type 'unsigned
	int *', but argument 4 has type 'int *' [-Wformat]

Signed-off-by: Sami Kerola <kerolasa@iki.fi>
include: fix void pointer arithmetics warnings

all-io.h:18:9: warning: pointer of type 'void *' used in arithmetic [-pedantic]
all-io.h:38:9: warning: pointer of type 'void *' used in arithmetic [-pedantic]

Signed-off-by: Sami Kerola <kerolasa@iki.fi>
partx: clarify up exclusive option handling

This commit will allow repetative exclusive options.

partx -s -s /dev/sda

And deny combination which earlier caused unexpected output.

partx -o NR -l /dev/sda

Signed-off-by: Sami Kerola <kerolasa@iki.fi>
docs: clean up partx.8 manual

* Remove bold & italic noise.
* Reformat text to be 70 characters wide.
* Use option and option argument highlights consistently.
* Indent option argument list for --nr.
* Squeeze examples where the same is done multiple different ways.
* Use URL and email macros where appropriate.

Signed-off-by: Sami Kerola <kerolasa@iki.fi>