chpst
changes the process state according to the given options, and runs
prog.
OPTIONS
-u [:]user[:group]
setuidgid.
Set uid and gid to the
user's
uid and gid, as found in
/etc/passwd.
If
user
is followed by a colon and a
group,
set the gid to
group's
gid, as found in
/etc/group,
instead of
user's
gid.
If
group
consists of a colon-separated list of group names,
chpst
sets the group ids of all listed groups.
If
user
is prefixed with a colon, the
user
and all
group
arguments are interpreted as uid and gids respectivly, and not looked up in
the password or group file.
All initial supplementary groups are removed.
-U [:]user[:group]
envuidgid.
Set the environment variables $UID and $GID to the
user's
uid and gid, as found in
/etc/passwd.
If
user
is followed by a colon and a
group,
set $GID to the
group's
gid, as found in
/etc/group,
instead of
user's
gid.
If
user
is prefixed with a colon, the
user
and
group
arguments are interpreted as uid and gid respectivly, and not looked up in
the password or group file.
-b argv0
argv0.
Run
prog
with
argv0
as the 0th argument.
-e dir
envdir.
Set various environment variables as specified by files in the directory
dir:
If
dir
contains a file named
k
whose first line is
v,
chpst
removes the environment variable
k
if it exists, and then adds the environment variable
k
with the value
v.
The name
k
must not contain =.
Spaces and tabs at the end of
v
are removed, and nulls in
v
are changed to newlines.
If the file
k
is empty (0 bytes long),
chpst
removes the environment variable
k
if it exists, without adding a new variable.
-/ root
chroot.
Change the root directory to
root
before starting
prog.
-n inc
nice.
Add
inc
to the
nice(2)
value before starting
prog.
inc
must be an integer, and may start with a minus or plus.
-l lock
lock.
Open the file
lock
for writing, and obtain an exclusive lock on it.
lock
will be created if it does not exist.
If
lock
is locked by another process, wait until a new lock can be obtained.
-L lock
The same as -l, but fail immediately if
lock
is locked by another process.
-m bytes
limit memory.
Limit the data segment, stack segment, locked physical pages, and total of
all segment per process to
bytes
bytes each.
-d bytes
limit data segment.
Limit the data segment per process to
bytes
bytes.
-o n
limit open files.
Limit the number of open file descriptors per process to
n.
-p n
limit processes.
Limit the number of processes per uid to
n.
-f bytes
limit output size.
Limit the output file size to
bytes
bytes.
-c bytes
limit core size.
Limit the core file size to
bytes
bytes.
-v
verbose.
Print verbose messages to standard error.
This includes warnings about limits unsupported by the system.
-P
pgrphack.
Run
prog
in a new process group.
-0
Close standard input before starting
prog.
-1
Close standard output before starting
prog.
-2
Close standard error before starting
prog.
EXIT CODES
chpst
exits 100 when called with wrong options.
It prints an error message and exits 111 if it has trouble changing the
process state.
Otherwise its exit code is the same as that of
prog.
EMULATION
If
chpst
is called as
envdir,
envuidgid,
pgrphack,
setlock,
setuidgid,
or
softlimit,
it emulates the functionality of these programs from the daemontools package
respectively.