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Linux

SENDMAIL-General Commands Manual

2017年08月05日

1 2	NAME - sendmail - Postfix to Sendmail compatibility interface

SYNOPSIS

sendmail [option ...] [recipient ...]

mailq
sendmail -bp

newaliases
sendmail -I

DESCRIPTION

The Postfix sendmail(1) command implements the Postfix to Sendmail com‐
patibility interface.  For the  sake  of  compatibility  with  existing
applications,  some  Sendmail  command-line  options are recognized but
silently ignored.

By default, Postfix sendmail(1) reads a  message  from  standard  input
until  EOF  or  until  it  reads  a  line  with only a . character, and
arranges for delivery.  Postfix sendmail(1) relies on  the  postdrop(1)
command to create a queue file in the maildrop directory.

Specific  command aliases are provided for other common modes of opera‐
tion:

mailq  List the mail queue. Each entry shows the queue file ID, message
       size,  arrival  time, sender, and the recipients that still need
       to be delivered.  If mail could not be delivered upon  the  last
       attempt, the reason for failure is shown. The queue ID string is
       followed by an optional status character:

       *      The message is in the active queue, i.e. the  message  is
              selected for delivery.

       !      The  message is in the hold queue, i.e. no further deliv‐
              ery attempt will be made until  the  mail  is  taken  off
              hold.

       This   mode   of  operation  is  implemented  by  executing  the
       postqueue(1) command.

newaliases
       Initialize the alias database.  If no input  file  is  specified
       (with  the  -oA  option,  see  below), the program processes the
       file(s) specified with the alias_database configuration  parame‐
       ter.   If  no alias database type is specified, the program uses
       the type specified with the default_database_type  configuration
       parameter.  This mode of operation is implemented by running the
       postalias(1) command.

       Note: it may take a minute or so before an alias database update
       becomes  visible.  Use the "postfix reload" command to eliminate
       this delay.

These and other features can be selected by specifying the  appropriate
combination  of  command-line  options. Some features are controlled by
parameters in the main.cf configuration file.

The following options are recognized:

-Am (ignored)

-Ac (ignored)
       Postfix sendmail uses the same configuration file regardless  of
       whether or not a message is an initial submission.

-B body_type
       The message body MIME type: 7BIT or 8BITMIME.

-bd    Go  into  daemon  mode. This mode of operation is implemented by
       executing the "postfix start" command.

-bh (ignored)

-bH (ignored)
       Postfix has no persistent host status database.

-bi    Initialize alias database. See the newaliases command above.

-bl    Go into daemon mode. To accept only local  connections  as  with
       Sendmail´s  -bl  option, specify "inet_interfaces = loopback" in
       the Postfix main.cf configuration file.

-bm    Read mail from standard input and arrange for delivery.  This is
       the default mode of operation.

-bp    List the mail queue. See the mailq command above.

-bs    Stand-alone  SMTP  server mode. Read SMTP commands from standard
       input, and write responses to standard output.   In  stand-alone
       SMTP  server  mode,  mail relaying and other access controls are
       disabled by default. To enable them,  run  the  process  as  the
       mail_owner user.

       This  mode  of  operation is implemented by running the smtpd(8)
       daemon.

-bv    Do not collect or deliver a  message.  Instead,  send  an  email
       report  after  verifying each recipient address.  This is useful
       for testing address rewriting and routing configurations.

       This feature is available in Postfix version 2.1 and later.

-C config_file

-C config_dir
       The path name of the Postfix main.cf  file,  or  of  its  parent
       directory.  This  information  is  ignored with Postfix versions
       before 2.3.

       With Postfix version 3.2 and later, a non-default directory must
       be  authorized  in  the default main.cf file, through the alter‐
       nate_config_directories  or  multi_instance_directories  parame‐
       ters.

       With  all Postfix versions, you can specify a directory pathname
       with the MAIL_CONFIG environment variable to override the  loca‐
       tion of configuration files.

-F full_name
       Set  the  sender  full name. This overrides the NAME environment
       variable, and is used only with messages that have no From: mes‐
       sage header.

-f sender
       Set  the  envelope  sender  address.  This  is the address where
       delivery problems are sent to. With Postfix versions before 2.1,
       the   Errors-To:  message  header  overrides  the  error  return
       address.

-G     Gateway (relay) submission, as opposed to initial  user  submis‐
       sion.   Either do not rewrite addresses at all, or update incom‐
       plete addresses  with  the  domain  information  specified  with
       remote_header_rewrite_domain.

       This option is ignored before Postfix version 2.3.

-h hop_count (ignored)
       Hop  count limit. Use the hopcount_limit configuration parameter
       instead.

-I     Initialize alias database. See the newaliases command above.

-i     When reading a message from standard input, don´t treat  a  line
       with only a . character as the end of input.

-L label (ignored)
       The  logging  label. Use the syslog_name configuration parameter
       instead.

-m (ignored)
       Backwards compatibility.

-N dsn (default: 'delay, failure')
       Delivery  status  notification   control.   Specify   either   a
       comma-separated list with one or more of failure (send notifica‐
       tion when delivery fails), delay (send notification when  deliv‐
       ery  is delayed), or success (send notification when the message
       is delivered); or specify never (don't send any notifications at
       all).

       This feature is available in Postfix 2.3 and later.

-n (ignored)
       Backwards compatibility.

-oAalias_database
       Non-default  alias  database. Specify pathname or type:pathname.
       See postalias(1) for details.

-O option=value (ignored)
       Set the named option to value. Use the equivalent  configuration
       parameter in main.cf instead.

-o7 (ignored)

-o8 (ignored)
       To  send 8-bit or binary content, use an appropriate MIME encap‐
       sulation and specify the appropriate -B command-line option.

-oi    When reading a message from standard input, don´t treat  a  line
       with only a . character as the end of input.

-om (ignored)
       The sender is never eliminated from alias etc. expansions.

-o x value (ignored)
       Set  option x to value. Use the equivalent configuration parame‐
       ter in main.cf instead.

-r sender
       Set the envelope sender  address.  This  is  the  address  where
       delivery problems are sent to. With Postfix versions before 2.1,
       the  Errors-To:  message  header  overrides  the  error   return
       address.

-R return
       Delivery  status notification control.  Specify "hdrs" to return
       only the header when a message bounces, "full" to return a  full
       copy (the default behavior).

       The -R option specifies an upper bound; Postfix will return only
       the header, when a full copy would exceed the  bounce_size_limit
       setting.

       This option is ignored before Postfix version 2.10.

-q     Attempt  to deliver all queued mail. This is implemented by exe‐
       cuting the postqueue(1) command.

       Warning: flushing undeliverable mail frequently will  result  in
       poor delivery performance of all other mail.

-qinterval (ignored)
       The interval between queue runs. Use the queue_run_delay config‐
       uration parameter instead.

-qIqueueid
       Schedule immediate delivery of mail with the specified queue ID.
       This  option  is  implemented by executing the postqueue(1) com‐
       mand, and is available with Postfix version 2.4 and later.

-qRsite
       Schedule immediate delivery of all mail that is queued  for  the
       named  site. This option accepts only site names that are eligi‐
       ble for the "fast flush" service, and is implemented by  execut‐
       ing the postqueue(1) command.  See flush(8) for more information
       about the "fast flush" service.

-qSsite
       This command is not implemented. Use the  slower  "sendmail  -q"
       command instead.

-t     Extract  recipients from message headers. These are added to any
       recipients specified on the command line.

       With Postfix versions prior to 2.1, this option requires that no
       recipient addresses are specified on the command line.

-U (ignored)
       Initial user submission.

-V envid
       Specify the envelope ID for notification by servers that support
       DSN.

       This feature is available in Postfix 2.3 and later.

-XV (Postfix 2.2 and earlier: -V)
       Variable Envelope Return Path. Given an envelope sender  address
       of  the  form  owner-listname@origin, each recipient user@domain
       receives mail with a personalized envelope sender address.

       By  default,  the  personalized  envelope  sender   address   is
       owner-listname+user=domain@origin.  The  default + and = charac‐
       ters are configurable with the default_verp_delimiters  configu‐
       ration parameter.

-XVxy (Postfix 2.2 and earlier: -Vxy)
       As  -XV,  but  uses  x  and  y as the VERP delimiter characters,
       instead of the characters specified with the default_verp_delim‐
       iters configuration parameter.

-v     Send an email report of the first delivery attempt (Postfix ver‐
       sions 2.1 and later). Mail delivery always happens in the  back‐
       ground.  When multiple -v options are given, enable verbose log‐
       ging for debugging purposes.

-X log_file (ignored)
       Log mailer traffic. Use the debug_peer_list and debug_peer_level
       configuration parameters instead.

SECURITY

1
2
3

By design, this program is not set-user (or group) id. However, it must
handle data from untrusted, possibly remote, users.   Thus,  the  usual
precautions need to be taken against malicious inputs.

DIAGNOSTICS

1	Problems are logged to syslogd(8) and to the standard error stream.

ENVIRONMENT

MAIL_CONFIG
       Directory with Postfix configuration files.

MAIL_VERBOSE (value does not matter)
       Enable verbose logging for debugging purposes.

MAIL_DEBUG (value does not matter)
       Enable debugging with an external command, as specified with the
       debugger_command configuration parameter.

NAME   The sender full name. This is used only with messages that  have
       no From: message header. See also the -F option above.

CONFIGURATION PARAMETERS

1
2
3

The  following  main.cf parameters are especially relevant to this pro‐
gram.  The text below provides only  a  parameter  summary.  See  post‐
conf(5) for more details including examples.

COMPATIBILITY CONTROLS

Available with Postfix 2.9 and later:

sendmail_fix_line_endings (always)
       Controls how the Postfix sendmail command converts email message
       line endings from <CR><LF> into UNIX format (<LF>).

TROUBLE SHOOTING CONTROLS

The DEBUG_README file gives examples of how to trouble shoot a  Postfix
system.

debugger_command (empty)
       The external command to execute when a Postfix daemon program is
       invoked with the -D option.

debug_peer_level (2)
       The increment in verbose logging level when a remote  client  or
       server matches a pattern in the debug_peer_list parameter.

debug_peer_list (empty)
       Optional  list  of  remote  client or server hostname or network
       address  patterns  that  cause  the  verbose  logging  level  to
       increase by the amount specified in $debug_peer_level.

ACCESS CONTROLS

Available in Postfix version 2.2 and later:

authorized_flush_users (static:anyone)
       List of users who are authorized to flush the queue.

authorized_mailq_users (static:anyone)
       List of users who are authorized to view the queue.

authorized_submit_users (static:anyone)
       List  of  users who are authorized to submit mail with the send‐
       mail(1) command (and with the privileged postdrop(1) helper com‐
       mand).

RESOURCE AND RATE CONTROLS

bounce_size_limit (50000)
       The  maximal  amount  of original message text that is sent in a
       non-delivery notification.

fork_attempts (5)
       The maximal number of attempts to fork() a child process.

fork_delay (1s)
       The delay between attempts to fork() a child process.

hopcount_limit (50)
       The maximal number of Received:  message headers that is allowed
       in the primary message headers.

queue_run_delay (300s)
       The  time  between  deferred  queue  scans by the queue manager;
       prior to Postfix 2.4 the default value was 1000s.

FAST FLUSH CONTROLS

The ETRN_README file describes configuration and operation details  for
the Postfix "fast flush" service.

fast_flush_domains ($relay_domains)
       Optional list of destinations that are eligible for per-destina‐
       tion logfiles with mail that is queued to those destinations.

VERP CONTROLS

The VERP_README file describes configuration and operation  details  of
Postfix support for variable envelope return path addresses.

default_verp_delimiters (+=)
       The two default VERP delimiter characters.

verp_delimiter_filter (-=+)
       The  characters  Postfix accepts as VERP delimiter characters on
       the Postfix sendmail(1) command line and in SMTP commands.

MISCELLANEOUS CONTROLS

alias_database (see 'postconf -d' output)
       The alias databases for local(8) delivery that are updated  with
       "newaliases" or with "sendmail -bi".

command_directory (see 'postconf -d' output)
       The location of all postfix administrative commands.

config_directory (see 'postconf -d' output)
       The  default  location of the Postfix main.cf and master.cf con‐
       figuration files.

daemon_directory (see 'postconf -d' output)
       The directory with Postfix support programs and daemon programs.

default_database_type (see 'postconf -d' output)
       The default database type for use in newaliases(1), postalias(1)
       and postmap(1) commands.

delay_warning_time (0h)
       The  time  after which the sender receives a copy of the message
       headers of mail that is still queued.

import_environment (see 'postconf -d' output)
       The list of environment parameters  that  a  privileged  Postfix
       process  will  import  from  a  non-Postfix  parent  process, or
       name=value environment overrides.

mail_owner (postfix)
       The UNIX system account that owns the  Postfix  queue  and  most
       Postfix daemon processes.

queue_directory (see 'postconf -d' output)
       The location of the Postfix top-level queue directory.

remote_header_rewrite_domain (empty)
       Don't  rewrite  message  headers from remote clients at all when
       this parameter is empty; otherwise, rewrite message headers  and
       append the specified domain name to incomplete addresses.

syslog_facility (mail)
       The syslog facility of Postfix logging.

syslog_name (see 'postconf -d' output)
       A  prefix  that  is  prepended  to  the  process  name in syslog
       records, so that, for example, "smtpd" becomes "prefix/smtpd".

Postfix 3.2 and later:

alternate_config_directories (empty)
       A list of non-default Postfix configuration directories that may
       be  specified with "-c config_directory" on the command line (in
       the case of sendmail(1), with  the  "-C"  option),  or  via  the
       MAIL_CONFIG environment parameter.

multi_instance_directories (empty)
       An  optional  list of non-default Postfix configuration directo‐
       ries; these directories belong to additional  Postfix  instances
       that  share  the Postfix executable files and documentation with
       the default Postfix instance, and  that  are  started,  stopped,
       etc., together with the default Postfix instance.

FILES

1 2	/var/spool/postfix, mail queue /etc/postfix, configuration files

SEE ALSO

pickup(8), mail pickup daemon
qmgr(8), queue manager
smtpd(8), SMTP server
flush(8), fast flush service
postsuper(1), queue maintenance
postalias(1), create/update/query alias database
postdrop(1), mail posting utility
postfix(1), mail system control
postqueue(1), mail queue control
syslogd(8), system logging

README_FILES

Use  "postconf readme_directory" or "postconf html_directory" to locate
this information.
DEBUG_README, Postfix debugging howto
ETRN_README, Postfix ETRN howto
VERP_README, Postfix VERP howto

LICENSE

1	The Secure Mailer license must be distributed with this software.

AUTHOR(S)

Wietse Venema
IBM T.J. Watson Research
P.O. Box 704
Yorktown Heights, NY 10598, USA

Wietse Venema
Google, Inc.
111 8th Avenue
New York, NY 10011, USA

LINUX

阅读全文

ps-man

2017年06月29日

1 2	NAME - ps -- process status

SYNOPSIS

1 2	ps [-AaCcEefhjlMmrSTvwXx] [-O fmt \| -o fmt] [-G gid[,gid...]] [-g grp[,grp...]] [-u uid[,uid...]] [-p pid[,pid...]] [-t tty[,tty...]] [-U user[,user...]] ps [-L]

DESCRIPTION

The ps utility displays a header line, followed by lines containing information about all of your processes that have controlling terminals.
A different set of processes can be selected for display by using any combination of the -a, -G, -g, -p, -T, -t, -U, and -u options.  If more than one of these options are given, then ps will select all processes which are matched by at least one of the given options.
For the processes which have been selected for display, ps will usually display one line per process.  The -M option may result in multiple output lines (one line per thread) for some processes.  By default all of these output lines are sorted first by controlling terminal, then by process ID.  The -m, -r, and -v options will change the sort order.  If more than one sorting option was given, then the selected processes will be sorted by the last sorting option which was specified.
For the processes which have been selected for display, the information to display is selected based on a set of keywords (see the -L, -O, and -o options).  The default output format includes, for each process, the process‘ ID, controlling terminal, CPU time (including both user and system time), state, and associated command.
The options are as follows:
-A      Display information about other users‘ processes, including those without controlling terminals.
-a      Display information about other users‘ processes as well as your own.  This will skip any processes which do not have a controlling terminal, unless the -x option is also specified.
-C      Change the way the CPU percentage is calculated by using a ``raw‘‘ CPU calculation that ignores ``resident‘‘ time (this normally has no effect).
-c      Change the ``command‘‘ column output to just contain the executable name, rather than the full command line.
-d      Like -A, but excludes session leaders.
-E      Display the environment as well.  This does not reflect changes in the environment after process launch.
-e      Identical to -A.
-f      Display the uid, pid, parent pid, recent CPU usage, process start time, controlling tty, elapsed CPU usage, and the associated command.  If the -u option is also used, display the user name rather then the numeric uid.  When -o or -O is used to add to the display following -f, the command field is not truncated as severely as it is in other formats.
-G      Display information about processes which are running with the specified real group IDs.
-g      Display information about processes with the specified process group leaders.
-h      Repeat the information header as often as necessary to guarantee one header per page of information.
-j      Print information associated with the following keywords: user, pid, ppid, pgid, sess, jobc, state, tt, time, and command.
-L      List the set of keywords available for the -O and -o options.
-l      Display information associated with the following keywords: uid, pid, ppid, flags, cpu, pri, nice, vsz=SZ, rss, wchan, state=S, paddr=ADDR, tty, time, and command=CMD.
-M      Print the threads corresponding to each task.
-m      Sort by memory usage, instead of the combination of controlling terminal and process ID.
-O      Add the information associated with the space or comma separated list of keywords specified, after the process ID, in the default information display.  Keywords may be appended with an equals (`=‘) sign and a string.  This causes the printed header to use the specified string instead of the standard header.
-o      Display information associated with the space or comma separated list of keywords specified.  Multiple keywords may also be given in the form of more than one -o option.  Keywords may be appended with an equals (`=‘) sign and a string.  This causes the printed header to use the specified string instead of the standard header.  If all keywords have empty header texts, no header line is written.
-p      Display information about processes which match the specified process IDs.
-r      Sort by current CPU usage, instead of the combination of controlling terminal and process ID.
-S      Change the way the process time is calculated by summing all exited children to their parent process.
-T      Display information about processes attached to the device associated with the standard input.
-t      Display information about processes attached to the specified terminal devices.
-U      Display the processes belonging to the specified real user IDs.
-u      Display the processes belonging to the specified usernames.
-v      Display information associated with the following keywords: pid, state, time, sl, re, pagein, vsz, rss, lim, tsiz, %cpu, %mem, and command.  The -v option implies the -m option.
-w      Use 132 columns to display information, instead of the default which is your window size.  If the -w option is specified more than once, ps will use as many columns as necessary without regard for your window size.  When output is not to a terminal, an unlimited number of columns are always used.
-X      When displaying processes matched by other options, skip any processes which do not have a controlling terminal.
-x      When displaying processes matched by other options, include processes which do not have a controlling terminal.  This is the opposite of the -X option.  If both -X and -x are specified in the same command, then ps will use the one which was specified last.
A complete list of the available keywords is given below.  Some of these keywords are further specified as follows:
%cpu      The CPU utilization of the process; this is a decaying average over up to a minute of previous (real) time.  Because the time base over which this is computed varies (some processes may be very young), it is possible for the sum of all %cpu fields to exceed 100%.
%mem      The percentage of real memory used by this process.
flags    The flags associated with the process as in the include file <sys/proc.h>:
          P_ADVLOCK           0x00001      Process may hold a POSIX advisory lock
          P_CONTROLT          0x00002      Has a controlling terminal
          P_LP64              0x00004      Process is LP64
          P_NOCLDSTOP         0x00008      No SIGCHLD when children stop
          P_PPWAIT            0x00010      Parent is waiting for child to exec/exit
          P_PROFIL            0x00020      Has started profiling
          P_SELECT            0x00040      Selecting; wakeup/waiting danger
          P_CONTINUED         0x00080      Process was stopped and continued
          P_SUGID             0x00100      Had set id privileges since last exec
          P_SYSTEM            0x00200      System proc: no sigs, stats or swapping
          P_TIMEOUT           0x00400      Timing out during sleep
          P_TRACED            0x00800      Debugged process being traced
          P_WAITED            0x01000      Debugging process has waited for child
          P_WEXIT             0x02000      Working on exiting
          P_EXEC              0x04000      Process called exec
          P_OWEUPC            0x08000      Owe process an addupc() call at next ast
          P_WAITING           0x40000      Process has a wait() in progress
          P_KDEBUG            0x80000        Kdebug tracing on for this process
lim      The soft limit on memory used, specified via a call to setrlimit(2).
lstart    The exact time the command started, using the `%c‘ format described in strftime(3).
nice      The process scheduling increment (see setpriority(2)).
rss      the real memory (resident set) size of the process (in 1024 byte units).
start    The time the command started.  If the command started less than 24 hours ago, the start time is displayed using the ``%l:ps.1p‘‘ format described in strftime(3).  If the command started less than 7 days ago, the start time is displayed using the ``%a6.15p‘‘ format.  Otherwise, the start time is displayed using the ``%e%b%y‘‘ format.
state    The state is given by a sequence of characters, for example, ``RWNA‘‘.  The first character indicates the run state of the process:
          I       Marks a process that is idle (sleeping for longer than about 20 seconds).
          R       Marks a runnable process.
          S       Marks a process that is sleeping for less than about 20 seconds.
          T       Marks a stopped process.
          U       Marks a process in uninterruptible wait.
          Z       Marks a dead process (a ``zombie‘‘).
          Additional characters after these, if any, indicate additional state information:
          +       The process is in the foreground process group of its control terminal.
          <       The process has raised CPU scheduling priority.
          >       The process has specified a soft limit on memory requirements and is currently exceeding that limit; such a process is (necessarily) not swapped.
          A       the process has asked for random page replacement (VA_ANOM, from vadvise(2), for example, lisp(1) in a garbage collect).
          E       The process is trying to exit.
          L       The process has pages locked in core (for example, for raw I/O).
          N       The process has reduced CPU scheduling priority (see setpriority(2)).
          S       The process has asked for FIFO page replacement (VA_SEQL, from vadvise(2), for example, a large image processing program using virtual memory to sequentially address voluminous data).
          s       The process is a session leader.
          V       The process is suspended during a vfork(2).
          W       The process is swapped out.
          X       The process is being traced or debugged.
tt        An abbreviation for the pathname of the controlling terminal, if any.  The abbreviation consists of the three letters following /dev/tty, or, for the console, ``con‘‘.  This is followed by a `-‘ if the process can no longer reach that controlling terminal (i.e., it has been revoked).
wchan    The event (an address in the system) on which a process waits.  When printed numerically, the initial part of the address is trimmed off and the result is printed in hex, for example, 0x80324000 prints as 324000.
When printing using the command keyword, a process that has exited and has a parent that has not yet waited for the process (in other words, a zombie) is listed as ``<defunct>‘‘, and a process which is blocked while trying to exit is listed as ``<exiting>‘‘.  If the arguments cannot be located (usually because it has not been set, as is the case of system processes and/or kernel threads) the command name is printed within square brackets.  The process can change the arguments shown with setproctitle(3).  Otherwise, ps makes an educated guess as to the file name and arguments given when the process was created by examining memory or the swap area.  The method is inherently somewhat unreliable and in any event a process is entitled to destroy this information.  The ucomm (accounting) keyword can, however, be depended on.  If the arguments are unavailable or do not agree with the ucomm keyword, the value for the ucomm keyword is appended to the arguments in parentheses.

KEYWORDS

The following is a complete list of the available keywords and their meanings.  Several of them have aliases (keywords which are synonyms).
%cpu      percentage CPU usage (alias pcpu)
%mem      percentage memory usage (alias pmem)
acflag    accounting flag (alias acflg)
args      command and arguments
comm      command
command    command and arguments
cpu        short-term CPU usage factor (for scheduling)
etime      elapsed running time
flags      the process flags, in hexadecimal (alias f)
gid        processes group id (alias group)
inblk      total blocks read (alias inblock)
jobc      job control count
ktrace    tracing flags
ktracep    tracing vnode
lim        memoryuse limit
logname    login name of user who started the session
lstart    time started
majflt    total page faults
minflt    total page reclaims
msgrcv    total messages received (reads from pipes/sockets)
msgsnd    total messages sent (writes on pipes/sockets)
nice      nice value (alias ni)
nivcsw    total involuntary context switches
nsigs      total signals taken (alias nsignals)
nswap      total swaps in/out
nvcsw      total voluntary context switches
nwchan    wait channel (as an address)
oublk      total blocks written (alias oublock)
p_ru      resource usage (valid only for zombie)
paddr      swap address
pagein    pageins (same as majflt)
pgid      process group number
pid        process ID
ppid      parent process ID
pri        scheduling priority
re        core residency time (in seconds; 127 = infinity)
rgid      real group ID
rss        resident set size
ruid      real user ID
ruser      user name (from ruid)
sess      session ID
sig        pending signals (alias pending)
sigmask    blocked signals (alias blocked)
sl        sleep time (in seconds; 127 = infinity)
start      time started
state      symbolic process state (alias stat)
svgid      saved gid from a setgid executable
svuid      saved UID from a setuid executable
tdev      control terminal device number
time      accumulated CPU time, user + system (alias cputime)
tpgid      control terminal process group ID
tsess      control terminal session ID
tsiz      text size (in Kbytes)
tt        control terminal name (two letter abbreviation)
tty        full name of control terminal
ucomm      name to be used for accounting
uid        effective user ID
upr        scheduling priority on return from system call (alias usrpri)
user      user name (from UID)
utime      user CPU time (alias putime)
vsz        virtual size in Kbytes (alias vsize)
wchan      wait channel (as a symbolic name)
wq        total number of workqueue threads
wqb        number of blocked workqueue threads
wqr        number of running workqueue threads
wql        workqueue limit status (C = constrained thread limit, T = total thread limit)
xstat      exit or stop status (valid only for stopped or zombie process)

ENVIRONMENT

1
2

The following environment variables affect the execution of ps:
COLUMNS  If set, specifies the user‘s preferred output width in column positions.  By default, ps attempts to automatically determine the terminal width.

FILES

/dev                 special files and device names
/var/run/dev.db      /dev name database
/var/db/kvm_kernel.db
                     system namelist database

LEGACY DESCRIPTION

In legacy mode, ps functions as described above, with the following differences:
-e      Display the environment as well. Same as -E.
-g      Ignored for compatibility. Takes no argument.
-l      Display information associated with the following keywords: uid, pid, ppid, cpu, pri, nice, vsz, rss, wchan, state, tt, time, and command.
-u      Display information associated with the following keywords: user, pid, %cpu, %mem, vsz, rss, tt, state, start, time, and command.  The -u option implies the -r option.
The biggest change is in the interpretation of the -u option, which now displays processes belonging to the specified username(s).  Thus, "ps -aux" will fail (unless you want to know about user "x").  As a convenience, however, "ps aux" still works as it did in Tiger.
For more information about legacy mode, see compat(5).

SEE ALSO

1	kill(1), w(1), kvm(3), strftime(3), sysctl(8)

STANDARDS

1	The ps utility supports the Version 3 of the Single UNIX Specification (``SUSv3‘‘) standard.

HISTORY

1	The ps command appeared in Version 4 AT&T UNIX.

BUGS

1
2

Since ps cannot run faster than the system and is run as any other scheduled process, the information it displays can never be exact.
The ps utility does not correctly display argument lists containing multibyte characters.

LINUX

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crontab-man

2017年01月05日

SYNOPSIS

1 2	crontab [ -u user ] file crontab [ -u user ] [ -i ] { -e \| -l \| -r }

DESCRIPTION

crontab  is  the  program used to install, deinstall or list the tables
used to drive the cron(8) daemon in Vixie Cron.   Each  user  can  have
their    own    crontab,    and    though    these    are    files   in
/var/spool/cron/crontabs, they are not intended to be edited directly.

If the /etc/cron.allow file exists, then you must be listed  (one  user
per  line)  therein in order to be allowed to use this command.  If the
/etc/cron.allow file does not exist but the  /etc/cron.deny  file  does
exist,  then you must not be listed in the /etc/cron.deny file in order
to use this command.

If neither of these files exists, then depending on site-dependent con‐
figuration  parameters, only the super user will be allowed to use this
command, or all users will be able to use this command.

If both files exist then /etc/cron.allow takes precedence. Which  means
that  /etc/cron.deny  is not considered and your user must be listed in
/etc/cron.allow in order to be able to use the crontab.

Regardless of the existance of any of these files, the root administra‐
tive  user  is  always allowed to setup a crontab.  For standard Debian
systems, all users may use this command.

If the -u option is given, it specifies the  name  of  the  user  whose
crontab  is  to  be  used (when listing) or modified (when editing). If
this option is not given, crontab examines "your"  crontab,  i.e.,  the
crontab  of the person executing the command.  Note that su(8) can con‐
fuse crontab and that if you are running inside  of  su(8)  you  should
always use the -u option for safety's sake.

The  first  form  of this command is used to install a new crontab from
some named file or standard  input  if  the  pseudo-filename  ``-''  is
given.

The  -l  option  causes the current crontab to be displayed on standard
output. See the note under DEBIAN SPECIFIC below.

The -r option causes the current crontab to be removed.

The -e option is used to edit the  current  crontab  using  the  editor
specified  by  the  VISUAL  or EDITOR environment variables.  After you
exit from the editor, the modified crontab will be installed  automati‐
cally.  If  neither  of  the environment variables is defined, then the
default editor /usr/bin/editor is used.

The -i option modifies the -r option to prompt the  user  for  a  'y/Y'
response before actually removing the crontab.

DEBIAN SPECIFIC

The  "out-of-the-box"  behaviour for crontab -l is to display the three
line "DO NOT EDIT THIS FILE" header that is placed at the beginning  of
the  crontab  when  it  is  installed. The problem is that it makes the
sequence

crontab -l | crontab -

non-idempotent -- you keep adding copies of  the  header.  This  causes
pain  to scripts that use sed to edit a crontab. Therefore, the default
behaviour of the -l option has been changed to not output such  header.
You  may obtain the original behaviour by setting the environment vari‐
able CRONTAB_NOHEADER to 'N', which will cause the crontab  -l  command
to emit the extraneous header.

SEE ALSO

1	crontab(5), cron(8)

FILES

/etc/cron.allow
/etc/cron.deny
/var/spool/cron/crontabs

There    is    one   file   for   each   user's   crontab   under   the
/var/spool/cron/crontabs directory. Users are not allowed to  edit  the
files  under  that directory directly to ensure that only users allowed
by the system to run periodic tasks can add them,  and  only  syntacti‐
cally correct crontabs will be written there.  This is enforced by hav‐
ing the directory writable only by the crontab  group  and  configuring
crontab command with the setgid bid set for that specific group.

STANDARDS

1
2
3

The  crontab command conforms to IEEE Std1003.2-1992 (``POSIX'').  This
new command syntax differs from previous versions  of  Vixie  Cron,  as
well as from the classic SVR3 syntax.

DIAGNOSTICS

A  fairly  informative  usage  message appears if you run it with a bad
command line.

cron requires that each entry in a crontab end in a newline  character.
If  the  last entry in a crontab is missing the newline, cron will con‐
sider the crontab (at least partially) broken and refuse to install it.

AUTHOR

1
2
3

Paul Vixie <paul@vix.com> is the author of cron and original creator of
this  manual page. This page has also been modified for Debian by Steve
Greenland, Javier Fernandez-Sanguino and Christian Kastner.

LINUX

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