readproctitle(8) System Manager's Manual readproctitle(8)NAME
readproctitle - maintains an automatically rotated log in memory for inspection by ps(1).
readproctitle is available in daemontools 0.75 and above.
readproctitle L D
L consists of any number of arguments. D is one argument consisting of at least five dots.
readproctitle reads data into the end of D, shifting D to the left to make room. This means that the most recent data is visible to
process-listing tools such as ps(1). readproctitle always leaves three dots at the left of D.
For example, if
readproctitle io errors: ....................
reads the data
fatal error xyz
then its command-line arguments change to
readproctitle io errors: ... xyz!warning abc!
with a newline character in place of each !. Process-listing tools typically show the newline character as ? or
readproctitle exits when it reaches the end of input.
Beware that most implementations of ps(1) have small argument-length limits. These limits apply to the total length of readproctitle L D.
I have not seen a system with a limit below 512 bytes.
SEE ALSO supervise(8), svc(8), svok(8), svstat(8), svscanboot(8), svscan(8), fghack(8), pgrphack(8), multilog(8), tai64n(8), tai64nlocal(8), setu-
idgid(8), envuidgid(8), envdir(8), softlimit(8), setlock(8), ps(1)
Check Out this Related Man Page
chpst(8) System Manager's Manual chpst(8)NAME
chpst - runs a program with a changed process state
chpst [-vP012] [-u user] [-U user] [-b argv0] [-e dir] [-/ root] [-n inc] [-l|-L lock] [-m bytes] [-d bytes] [-o n] [-p n] [-f bytes] [-c
prog consists of one or more arguments.
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.
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.
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.
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.
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.
The same as -l, but fail immediately if lock is locked by another process.
limit memory. Limit the data segment, stack segment, locked physical pages, and total of all segment per process to bytes 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.
limit output size. Limit the output file size to bytes 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.
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.
If chpst is called as envdir, envuidgid, pgrphack, setlock, setuidgid, or softlimit, it emulates the functionality of these programs from
the daemontools package respectively.
SEE ALSO sv(8), runsv(8), setsid(2), runit(8), runit-init(8), runsvdir(8), runsvchdir(8)
Gerrit Pape <firstname.lastname@example.org>