after playing a little with android, it happens that my hdd went full !!! apparently the tmp directory is growing fast as you use android... i notice it is erased on android launch but is it safe to erase it as android is running 
Good point, jpmatrix.
I tried
ls on android-root/tmp.
[div class=\'codetop\']CODE[/div][div class=\'codemain\' style=\'height:200px;white-space:pre;overflow:auto\']
-rw------- root root 11429 2008-01-07 23:37 eventlog
srwxrwxrwx root root 2008-01-07 23:36 system_bus_socket
-rw-r--r-- root root 5 2008-01-07 23:36 messagebus.pid
prw--w--w- root root 2008-01-07 23:43 android-SurfaceFlingerSynchro
-rw-r--r-- root root 4096 2008-01-07 23:37 android-shared_heap.1864.0x157f80
-rw-r--r-- app_0 app_0 23552 2008-01-07 23:37 media.db
-rw-rw-rw- root root 9838592 2008-01-07 23:37 android-shared_heap.1864.0x189b90
-rw-rw-rw- app_4 app_4 1048576 2008-01-07 23:37 android-shared_heap.1897.0x15df98
-rw-r--r-- app_0 app_0 12288 2008-01-07 23:37 im_transient.db
-rw-rw-rw- phone phone 1048576 2008-01-07 23:38 android-shared_heap.1899.0x18f678
-rw-r--r-- app_0 app_0 2048 2008-01-07 23:37 contacts_presence.db
-rw-rw-rw- root root 9838592 2008-01-07 23:37 android-shared_heap.1864.0x1b1c80
-rw-rw-rw- phone phone 1048576 2008-01-07 23:38 android-shared_heap.1899.0x186ba0
-rw-rw-rw- root root 9838592 2008-01-07 23:38 android-shared_heap.1864.0x1a4088
-rw-rw-rw- phone phone 1048576 2008-01-07 23:38 android-shared_heap.1899.0x1947b8
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Each Android applet eats 1M to 9M bytes shared memory and they are put in /tmp. I guess Dalvik VM does this trick. Obviously you can't delete them on runtime.
For a real target device, /tmp is usually assigned to ramfs. Our Android Zaurus case, it's on internal hdd/flash filesystem. I've been wondering why Android runs on poor 64M, but shared memory on /tmp explains a little.
On the other hand, if android-root/tmp goes to ramfs, Android Zaurus may run much faster. There's always bright side.
By the way,
start-android script erases android-root/tmp each time at startup. The reason is binderdev.o reports warning if
messagebus.pid[/] exists in android-root/tmp at boot up. So I decided clean them up all in start script. Well, it's supposed to be volatile anyway.
Cheers,