shinit

commit 8f51b17ed0b38b12bb2da6d561d9a53a5301b5ec
parent 11c4f9b3a6c6665455ec0c3c929843c167fa6615
Author: Cem Keylan <cem@ckyln.com>
Date:   Fri, 17 Jul 2020 14:59:01 +0300

README: update

Diffstat:
M
README.md
 | 
44
++++++++++++++++++++++++++++++++++++++++----

1 file changed, 40 insertions(+), 4 deletions(-)
diff --git a/README.md b/README.md
@@ -1,8 +1,8 @@
 shinit
 ======
 
-Basic init daemon in POSIX sh with only 5 lines of code. It supports
-acting upon signals.
+Basic init daemon in POSIX sh with only 5 lines of code. It supports acting upon
+signals.
 
 On USR1 signal it will poweroff, and on INT signal it will reboot.
 
@@ -10,9 +10,45 @@ On USR1 signal it will poweroff, and on INT signal it will reboot.
 Installing
 ----------
 
-Before installing, edit the second command to use your boot/poweroff
-script. If you are using Carbs Linux or KISS, you don't need to change it.
+Before installing, edit the second command to use your boot/poweroff script. If
+you are using Carbs Linux or KISS, you don't need to change it.
 
 You can then install with `make`.
 
     make install
+
+
+Note on halting the system
+--------------------------
+
+shinit does **NOT** deal with system halting. You will need an extra utility for
+that given purpose. `ubase halt` deals with this. You can also use compile
+this really simple C program that tells to kernel to shutdown or reboot.
+
+``` c
+#include <sys/reboot.h>
+
+int
+main(int argc, char *argv[])
+{
+    switch ((int) argv[argc < 2 ? 0 : 1][0]) {
+    case 'p': reboot(RB_POWER_OFF); break;
+    case 'r': reboot(RB_AUTOBOOT);  break;
+    default: return 1;
+    }
+    return 0;
+}
+```
+
+You can compile the following program to something named `halt` or whatever you
+like. If you call `halt p` it will power off, if you call `halt r` it will
+reboot. Just note that this needs to be at the end of your init script, because
+this command will shut your computer down straight away. You can do the
+following check at the end of your init script:
+
+``` sh
+case "$1" in
+    poweroff) halt p ;;
+    reboot)   halt r ;;
+esac
+```