logread: flush output. closes 6710

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
logread: don't call shmdt() before exit, kernel does it for us.

function                                             old     new   delta
logread_main                                         472     466      -6
interrupted                                           20       9     -11
error_exit                                            20       -     -20
------------------------------------------------------------------------------
(add/remove: 0/1 grow/shrink: 0/2 up/down: 0/-37)             Total: -37 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
build system: do not generate MAX_APPLET_NAME_LEN (unused)

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
devfsd: remove static variable

function                                             old     new   delta
static.msg                                             4       -      -4
get_uid_gid                                          114     107      -7
------------------------------------------------------------------------------
(add/remove: 0/1 grow/shrink: 0/1 up/down: 0/-11)             Total: -11 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
libbb: add sketch of tentative 'better' passwd/group API

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
init: halt on SIGPWR too

Most init processes implement a handler for SIGPWR that gracefully
stops all child processes when shutting down a machine. Some other
technologies rely on this signal - e.g. Busybox powered LXC
containers.

This patch makes busybox init halt when receiving SIGPWR.

Signed-off-by: Bogdan Purcareata <bogdan.purcareata@freescale.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
build system: use od -b instead of od -t x1

od -t is not available in non-CONFIG_DESKTOPed busybox od

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>