HelenOS sources

sys_perm_revoke    78 kernel/generic/include/security/perm.h extern sys_errno_t sys_perm_revoke(uspace_ptr_sysarg64_t, perm_t);
sys_perm_revoke    85 kernel/generic/include/security/perm.h extern sys_errno_t sys_perm_revoke(sysarg_t, perm_t);
sys_perm_revoke   111 kernel/generic/src/syscall/syscall.c 	[SYS_PERM_REVOKE] = (syshandler_t) sys_perm_revoke,