This is a legacy interface from 4.4BSD, and it was
introduced to overcome shortcomings of ptrace(2) at that time, which are
no longer relevant (performance). Today /proc/#/ctl offers a narrow
subset of ptrace(2) commands and is not applicable for modern
applications use beyond simplistic tracing scenarios.
This removal will simplify kernel internals. Users will still be able to
use all the other /proc files.
This change won't affect other procfs files neither Linux compat
features within mount_procfs(8). /proc/#/ctl isn't available on Linux.
Remove:
- /proc/#/ctl from mount_procfs(8)
- P_FSTRACE note from the documentation of ps(1)
- /proc/#/ctl and filesystem tracing documentation from mount_procfs(8)
- KAUTH_REQ_PROCESS_PROCFS_CTL documentation from kauth(9)
- source code file miscfs/procfs/procfs_ctl.c
- PFSctl and procfs_doctl() from sys/miscfs/procfs/procfs.h
- KAUTH_REQ_PROCESS_PROCFS_CTL from sys/sys/kauth.h
- PSL_FSTRACE (0x00010000) from sys/sys/proc.h
- P_FSTRACE (0x00010000) from sys/sys/sysctl.h
Reduce code complexity after removal of this functionality.
Update TODO.ptrace accordingly: remove two entries about /proc tracing.
Do not keep legacy notes as comments in the headers about removed
PSL_FSTRACE / P_FSTRACE, as this interface had little number of users
(close or equal to zero).
Proposed on tech-kern@.
All filesystem tracing utility users are encouraged to switch to ptrace(2).
Sponsored by <The NetBSD Foundation>
because the -o linux flag was not supplied, i.e. it is the sensible
default. People who absolutely do not want the extra files in
their /proc for whatever aesthetic reason (it's not like they
consume any resources) can do -o nolinux.
systems just checked != 0, breaking MNT_GETARGS. Others worked with < 0,
but make them check against -1 too for consistency. And sprinkle some
stylish line wrapping where appropriate.
link points to the process's current working directory, and the root
link points to the process's root directory. What else would you
expect?
For directories that are out of reach (caller is in a chroot, target
process is in a different chroot, etc), the links point to "/"
instead.
* make static all symbols which do not need to be exported
* rename main() to mount_FOO()
* new main() now just calls mount_FOO(), main() is only compiled in if
MOUNT_NOMAIN is not defined
* a_gid(), a_uid() and a_mask() were put into ../mount/fattr.[ch], local
versions removed
