filesytem 的 uid/gid : AID_XXXX 定義在 system/core/include/private/android_filesystem_config.h

/* This is the master Users and Groups config for the platform.
 * DO NOT EVER RENUMBER
 */

#define AID_ROOT             0  /* traditional unix root user */

#define AID_SYSTEM        1000  /* system server */

#define AID_RADIO         1001  /* telephony subsystem, RIL */
#define AID_BLUETOOTH     1002  /* bluetooth subsystem */
#define AID_GRAPHICS      1003  /* graphics devices */
#define AID_INPUT         1004  /* input devices */
#define AID_AUDIO         1005  /* audio devices */
#define AID_CAMERA        1006  /* camera devices */
#define AID_LOG           1007  /* log devices */
#define AID_COMPASS       1008  /* compass device */
#
...
...
#define AID_EVERYBODY     9997  /* shared between all apps in the same profile */
#define AID_MISC          9998  /* access to misc storage */
#define AID_NOBODY        9999

#define AID_APP          10000  /* first app user */