all: updates for for-each

Signed-off-by: Drew DeVault <sir@cmpwn.com>

update for hare stdlib changes

Fix build with Hare ^HEAD

Signed-off-by: Carlos Une <une@fastmail.fm>

Phony target unintall -> uninstall

Fix chmod permissions

Minor style improvement

sysfs: s/write_state/write_sysfs_file

Rename write_state() to write_sysfs_file() and use it everywhere.

Signed-off-by: Jose Lombera <jose@lombera.dev>

sysfs: reuse parsing logic in several places

Signed-off-by: Jose Lombera <jose@lombera.dev>

sysfs: use simple unbuffered writes

Signed-off-by: Jose Lombera <jose@lombera.dev>

Makefile: small enhancements

- powerctl is not a PHONY target.
- Add dependencies to targets powerctl and install.
- Add clean and uninstall targets.

Signed-off-by: Jose Lombera <jose@lombera.dev>

README: reference powerctl(8)

Signed-off-by: Jose Lombera <jose@lombera.dev>

checkgroup: fix error message

Makefile: set PREFIX to /usr/local by default

set_sleep_state: drop rt::sync

The kernel does this for us via /sys/power/sync_on_suspend.

sysfs: streamline buffer usage

set_sleep_state: rt::sync always succeeds

Makefile: specificy hare build output

Add man page

checkgroup: simplify implementation

This also improves performance by avoiding repeated scans over
/etc/group

Implement set image size