1.\" Copyright (C) 1996 2.\" David L. Nugent. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 13.\" THIS SOFTWARE IS PROVIDED BY DAVID L. NUGENT AND CONTRIBUTORS ``AS IS'' AND 14.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16.\" ARE DISCLAIMED. IN NO EVENT SHALL DAVID L. NUGENT OR CONTRIBUTORS BE LIABLE 17.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23.\" SUCH DAMAGE. 24.\" 25.\" $Id: pw.8,v 1.4 1996/12/11 00:07:19 joerg Exp $ 26.\" 27.Dd December 9, 1996 28.Dt PW 8 29.Os 30.Sh NAME 31.Nm pw 32.Nd create, remove, modify & display system users and groups 33.Sh SYNOPSIS 34.Nm pw 35.Ar useradd 36.Op name|uid 37.Op Fl C Ar config 38.Op Fl q 39.Op Fl n Ar name 40.Op Fl u Ar uid 41.Op Fl c Ar comment 42.Op Fl d Ar dir 43.Op Fl e Ar date 44.Op Fl p Ar date 45.Op Fl g Ar group 46.Op Fl G Ar grouplist 47.Op Fl m 48.Op Fl k Ar dir 49.Op Fl s Ar shell 50.Op Fl o 51.Op Fl L Ar class 52.Op Fl h Ar fd 53.Op Fl N 54.Op Fl P 55.Nm pw 56.Ar useradd 57.Op name|uid 58.Op Fl D 59.Op Fl C Ar config 60.Op Fl q 61.Op Fl b Ar dir 62.Op Fl e Ar days 63.Op Fl p Ar days 64.Op Fl g Ar group 65.Op Fl G Ar grouplist 66.Op Fl k Ar dir 67.Op Fl u Ar min,max 68.Op Fl i Ar min,max 69.Op Fl w Ar method 70.Op Fl s Ar shell 71.Nm pw 72.Ar userdel 73.Op name|uid 74.Op Fl n Ar name 75.Op Fl u Ar uid 76.Op Fl r 77.Nm pw 78.Ar usermod 79.Op name|uid 80.Op Fl C Ar config 81.Op Fl q 82.Op Fl n Ar name 83.Op Fl u Ar uid 84.Op Fl c Ar comment 85.Op Fl d Ar dir 86.Op Fl e Ar date 87.Op Fl p Ar date 88.Op Fl g Ar group 89.Op Fl G Ar grouplist 90.Op Fl l Ar name 91.Op Fl m 92.Op Fl k Ar dir 93.Op Fl w Ar method 94.Op Fl s Ar shell 95.Op Fl L Ar class 96.Op Fl h Ar fd 97.Op Fl N 98.Op Fl P 99.Nm pw 100.Ar usershow 101.Op name|uid 102.Op Fl n Ar name 103.Op Fl u Ar uid 104.Op Fl F 105.Op Fl P 106.Op Fl a 107.Nm pw 108.Ar usernext 109.Op Fl C Ar config 110.Op Fl q 111.Nm pw 112.Ar groupadd 113.Op group|gid 114.Op Fl C Ar config 115.Op Fl q 116.Op Fl n Ar group 117.Op Fl g Ar gid 118.Op Fl M Ar members 119.Op Fl o 120.Op Fl h Ar fd 121.Op Fl N 122.Op Fl P 123.Nm pw 124.Ar groupdel 125.Op Fl n Ar name 126.Op Fl g Ar gid 127.Nm pw 128.Ar groupmod 129.Op Fl C Ar config 130.Op Fl q 131.Op Fl F 132.Op Fl n Ar name 133.Op Fl g Ar gid 134.Op Fl l Ar name 135.Op Fl M Ar members 136.Op Fl m Ar newmembers 137.Op Fl h Ar fd 138.Op Fl N 139.Op Fl P 140.Nm pw 141.Ar groupshow 142.Op Fl n Ar name 143.Op Fl g Ar gid 144.Op Fl F 145.Op Fl P 146.Op Fl a 147.Nm pw 148.Ar groupnext 149.Op Fl C Ar config 150.Op Fl q 151.Sh DESCRIPTION 152.Nm pw 153is a command-line based editor for the system 154.Em user 155and 156.Em group 157files, allowing the superuser and easy to use and standardized way of adding, 158modifying and removing users and groups. 159Note that 160.Nm pw 161only operates on the local user and group files; NIS users and groups must be 162maintained on the NIS server. 163.Nm pw 164handles updating the 165.Pa passwd , 166.Pa master.passwd , 167.Pa group 168and the secure and insecure 169password database files, and must be run as root. 170.Pp 171The first one or two keywords provided on 172.Xr pw 8 's 173command line provide the context for the remainder of the arguments. 174One of the keywords 175.Ar user 176and 177.Ar group 178may be combined or provided separately with 179.Ar add , 180.Ar del , 181.Ar mod , 182.Ar show , 183or 184.Ar next , 185and may be specified in either order (ie. showuser, usershow, show user and user show 186are all considered to be the same thing). 187This flexibility is useful for interactive scripts which call 188.Nm pw 189for the actual user and group database manipulation. 190Following these keywords, you may optionally specify the user or group name or numeric 191id as an alternative to using the 192.Fl n Ar name , 193.Fl u Ar uid , 194.Fl g Ar gid 195options. 196.Pp 197The following flags are common to all modes of operation: 198.Pp 199.Bl -tag -width "-G grouplist" 200.It Fl C Ar config 201By default, 202.Nm pw 203reads the file 204.Pa /etc/pw.conf 205to obtain policy information on how new user accounts and groups are to be created, 206and the 207.Fl C 208option specifies a different configuration file. 209Most of the contents in the configuration file may be overridden via command line 210options, but it may be more useful to set up standard information for addition of 211new accounts in the configuration file. 212.It Fl q 213Use of this option causes 214.Nm pw 215to suppress error messages, which may be useful in interactive environments where it 216is preferable to interpret status codes returned by 217.Nm pw 218rather than messing up a carefully formatted display. 219.It Fl N 220This option is available in add and modify operations, and causes 221.Nm pw 222to skip updating the user/group databases and instead print the result 223of the operation without actually performing it. 224You may use the 225.Fl P 226option to switch between standard passwd and readable formats. 227.El 228.Pp 229.Sh USER OPTIONS 230The following options apply to the 231.Ar useradd , 232and 233.Ar usermod , 234commands: 235.Pp 236.Bl -tag -width "-G grouplist" 237.It Fl n Ar name 238Specifies the user/account name. 239.It Fl u Ar uid 240Specifies the user/account numeric id. 241.Pp 242Usually, you need only to provide one or the other of these options, as the account 243name will imply the uid, and vice versa. 244Also, you may provide either the account or userid immediately after the 245.Ar useradd , 246.Ar userdel , 247.Ar usermod 248or 249.Ar usershow 250keyword on the command line without the need to use 251.Ql Fl n 252or 253.Ql Fl u . 254There are times, however, were you need to provide both. 255For example, when changing the uid of an existing user with 256.Ar usermod , 257or overriding the default uid when creating a new account. 258If you wish 259.Nm pw 260to automatically allocate the uid to a new user on 261.Ar useradd , 262then you should 263.Em not 264use the 265.Ql Fl u 266option. 267.El 268.Pp 269Options available with both 270.Ar useradd 271and 272.Ar usermod 273are: 274.Bl -tag -width "-G grouplist" 275.It Fl c Ar comment 276This field sets the contents of the passwd GECOS field, which normally contains up 277to four comma-separated fields containing the user's full name, office or location, 278work and home phone numbers. 279These sub-fields are used by convention only, however, and are optional. 280If this field is to contain spaces, you need to quote the comment itself with double 281quotes 282.Ql \&" . 283Avoid using commas in this field as these are used as sub-field separators, and the 284colon 285.Ql \&: 286character also cannot be used as this is the field separator in the passwd file. 287.It Fl d Ar dir 288This option sets the account's home directory. 289Normally, you will only use this if the home directory is to be different from the 290default (which is determined from pw.conf, which specifies the base home directory 291- normally /home - with the account name as a subdirectory). 292.It Fl e Ar date 293Sets the account's expiration date. 294Format of the date is either a UNIX time in decimal, or a date in 295.Ql \& dd-mmm-yy[yy] 296format, where dd is the day, mmm is the month, either in numeric or alphabetic format 297('Jan', 'Feb' etc) and year is either a two or four digit year. 298This option also accepts a relative date in the form 299.Ql \&+n[mhdwoy] 300where 301.Ql \&n 302is a decimal, octal (leading 0) or hexadecimal (leading 0x) digit followed by the 303number of Minutes, Hours, Days, Weeks, Months or Years from the current date at 304which the expiry date is to be set. 305.It Fl p Ar date 306Sets the account's password expiration date. 307This field is identical to the account expiration date option, except that it 308applies to forced password changes. 309The same formats are accepted as with the account expiration option. 310.It Fl g Ar group 311Sets the account's primary group to the given group. 312.Ar group 313may be either the group name or its corresponding group id number. 314.It Fl G Ar grouplist 315Sets the additional groups to which an account belongs. 316.Ar grouplist 317is a comma-separated list or group names or group ids. 318When adding a user, the user's name is added to the group lists in 319.Pa /etc/group , 320and when editing a user, the user's name is also added to the group lists, and 321removed from any groups not specified in 322.Ar grouplist . 323Note: a user should not be added to their primary group in 324.Pa /etc/group . 325Also, group membership changes do not take effect immediately for current logins, 326only logins subsequent to the change. 327.It Fl L Ar class 328This option sets the login class for the user being created. 329See 330.Xr login.conf 5 331for more information on user classes. 332.It Fl m 333This option instructs 334.Nm pw 335to attempt to create the user's home directory. 336While primarily useful when adding a new account with 337.Ar useradd , 338this may also be of use when moving an existing user's home directory elsewhere on 339the filesystem. 340The new home directory is populated with the contents of the 341.Ar skeleton 342directory, which typically contains a set of shell configuration files that the 343user may personalize to taste. 344When 345.Ql Fl m 346is used on an account with 347.Ar usermod , 348any existing configuration files in the user's home directory are 349.Em not 350overwritten with the prototype files. 351.Pp 352When a user's home directory is created, it will be default be as a subdirectory of the 353.Ar basehome 354directory specified with the 355.Ql Fl b Ar dir 356option (see below), and will be named the same as the account. 357This may be overridden with the 358.Ql Fl d Ar dir 359option on the command line, if desired. 360.It Fl k Ar dir 361Sets the 362.Ar skeleton 363subdirectory, from which the basic startup and configuration files are copied when 364the user's home directory is created. 365This option only has meaning when used with 366.Ql Fl D 367(see below) or 368.Ql Fl m . 369.It Fl s Ar shell 370Sets or changes the user's login shell to 371.Ar shell . 372If the path to the shell program is omitted, 373.Nm pw 374searches the 375.Ar shellpath 376specified in 377.Pa /etc/pw.conf 378and fills it in as appropriate. 379Note that unless you have a specific reason to do so, you should avoid 380specifying the path - this will allow 381.Nm pw 382to validate that the program exists and is executable. 383Specifying a full path (or supplying a blank "" shell) avoids this check 384and allows for such entries as 385.Ql \& /nonexistent 386that should be set for accounts not intended for interactive login. 387.It Fl L Ar class 388Sets the 389.Em class 390field in the user's passwd record. 391This field is not currently used, but will be in the future used to specify a 392.Em termcap 393entry like tag (see 394.Xr passwd 5 395for details). 396.It Fl h Ar fd 397This option provides a special interface by which interactive scripts can 398set an account password using 399.Nm pw . 400Because the command line and environment are fundamental insecure mechanisms 401by which programs can accept information, 402.Nm pw 403will only allow setting of account and group passwords via a file descriptor 404(usually a pipe between an interactive script and the program). 405.Ar sh , 406.Ar bash , 407.Ar ksh 408and 409.Ar perl 410all posses mechanisms by which this can be done. 411Alternatively, 412.Nm pw 413will prompt for the user's password if 414.Ql Fl h Ar 0 415is given, nominating 416.Em stdin 417as the file descriptor on which to read the password. 418Note that this password will be read once and once only and is intended 419for use by a script or similar rather than interactive use. 420If you wish to have new password confirmation along the lines of 421.Xr passwd 1 , 422this must be implemented as part of the interactive script that calls 423.Nm pw . 424.Pp 425If a value of 426.Ql \&- 427is given as the argument 428.Ar fd , 429then the password will be set to 430.Ql \&* , 431rendering the account inaccessible via passworded login. 432.El 433.Pp 434It is possible to use 435.Ar useradd 436to create a new account that duplicates an existing user id. 437While this is normally considered an error and will be rejected, the 438.Ql Fl o 439option overrides the check for duplicates and allows the duplication of 440the user id. 441This may be useful if you allow the same user to login under 442different contexts (different group allocations, different home 443directory, different shell) while providing basically the same 444permissions for access to the user's files in each account. 445.Pp 446The 447.Ar useradd 448command also has the ability to set new user and group defaults by using the 449.Ql Fl D 450option. 451Instead of adding a new user, 452.Nm pw 453writes a new set of defaults to its configuration file, 454.Pa /etc/pw.conf . 455When using the 456.Ql Fl D 457option, you must not use either 458.Ql Fl n Ar name 459or 460.Ql Fl u Ar uid 461or an error will result. 462Use of 463.Ql Fl D 464changes the meaning of several command line switches in the 465.Ar useradd 466command. 467These are: 468.Bl -tag -width "-G grouplist" 469.It Fl D 470Set default values in 471.Pa /etc/pw.conf 472configuration file, or a different named configuration file if the 473.Ql Fl C Ar config 474option is used. 475.It Fl b Ar dir 476Sets the root directory in which user home directories are created. 477The default value for this is 478.Ql \&/home , 479but it may be set elsewhere as desired. 480.It Fl e Ar days 481Sets the default account expiration period in days. 482Unlike use without 483.Ql Fl D , 484the argument must be numeric, which specifies the number of days after creation when 485the account is to expire. 486A value of 0 suppresses automatic calculation of the expiry date. 487.It Fl p Ar days 488Sets the default password expiration period in days. 489.It Fl g Ar group 490Sets the default group for new users. 491If a blank group is specified using 492.Ql Fl g Ar \&"" , 493then new users will be allocated their own private primary group (a new group created 494with the same name as their login name). 495If a group is supplied, either its name or uid may be given as an argument. 496.It Fl G Ar grouplist 497Sets the default groups in which new users are made members. 498This is a separate set of groups from the primary group, and you should avoid 499nominating the same group as both the primary and in extra groups. 500In other words, these extra groups determine membership in groups 501.Em other than 502the primary group. 503.Ar grouplist 504is a comma-separated list of group names or ids, or a mixture of both, and are always 505stored in 506.Pa /etc/pw.conf 507by their symbolic names. 508.It Fl L Ar class 509This option sets the default login class for new users. 510.It Fl k Ar dir 511Sets the default 512.Em skeleton 513directory, from which prototype shell and other initialization files are copied when 514.Nm pw 515creates a user's home directory. 516.It Fl u Ar min,max , Fl i Ar min,max 517These options set the minimum and maximum user and group ids allocated for new accounts 518and groups created by 519.Nm pw . 520The default values for each is 1000 minimum and 32000 maximum. 521.Ar min 522and 523.Ar max 524are both numbers, where max must be greater than min, and both must be between 0 525and 32767. 526In general, user and group ids less than 100 are reserved for use by the system, 527and numbers greater than 32000 may also be reserved for special purposes (used by 528some system daemons). 529.It Fl w Ar method 530The 531.Ql Fl w 532option sets the default method used to set passwords for newly created user accounts. 533.Ar method 534is one of: 535.Pp 536.Bl -tag -width random -offset indent -compact 537.It no 538disables login on newly created accounts 539.It yes 540forces the password to be the account name 541.It none 542forces a blank password 543.It random 544Generates a random password 545.El 546.Pp 547The 548.Ql \&random 549or 550.Ql \&no 551methods are the most secure; in the former case, 552.Nm pw 553generates a password and prints it to stdout, which is suitable where you issue 554users with passwords to access their accounts rather than having the user nominate 555their own (possibly poorly chosen) password. 556The 557.Ql \&no 558method requires that the superuser use 559.Xr passwd 1 560to render the account accessible with a password. 561.El 562.Pp 563The 564.Ar userdel 565command has only three valid options. The 566.Ql Fl n Ar name 567and 568.Ql Fl u Ar uid 569options have already been covered above. 570The additional option is: 571.Bl -tag -width "-G grouplist" 572.It Fl r 573This tells 574.Nm pw 575to remove the user's home directory and all of its contents. 576.Nm pw 577errs on the side of caution when removing files from the system. 578Firstly, it will not do so if the uid of the account being removed is also used by 579another account on the system, and the 'home' directory in the password file is 580a valid path that commences with the character 581.Ql \&/ . 582Secondly, it will only remove files and directories that are actually owned by 583the user, or symbolic links owned by anyone under the user's home directory. 584Finally, after deleting all contents owned by the user only empty directories 585will be removed. 586If any additional cleanup work is required, this is left to the administrator. 587.El 588.Pp 589Mail spool files and crontabs are always removed when an account is deleted as these 590are unconditionally attached to the user name. 591Jobs queued for processing by 592.Ar at 593are also removed if the user's uid is unique (not also used by another account on the 594system). 595.Pp 596The 597.Ar usershow 598command allows viewing of an account in one of two formats. 599By default, the format is identical to the format used in 600.Pa /etc/master.passwd 601with the password field replaced with a 602.Ql \&* . 603If the 604.Ql Fl P 605option is used, then 606.Nm pw 607outputs the account details in a more human readable form. 608The 609.Ql Fl a 610option lists all users currently on file. 611.Pp 612The command 613.Ar usernext 614returns the next available user and group ids separated by a colon. 615This is normally of interest only to interactive scripts or front-ends 616that use 617.Nm pw . 618.Pp 619.Sh GROUP OPTIONS 620The 621.Ql Fl C Ar config 622and 623.Ql Fl q 624options (explained at the start of the previous section) are available 625with the group manipulation commands. 626Other common options to all group-related commands are: 627.Bl -tag -width "-m newmembers" 628.It Fl n Ar name 629Specifies the group name. 630.It Fl g Ar gid 631Specifies the group numeric id. 632.Pp 633As with the account name and id fields, you will usually only need 634to supply one of these, as the group name implies the uid and vice 635versa. 636You will only need to use both when setting a specific group id 637against a new group or when changing the uid of an existing group. 638.It Fl M Ar memberlist 639This option provides an alternative way to add existing users to a 640new group (in groupadd) or replace an existing membership list (in 641groupmod). 642.Ar memberlist 643is a comma separated list of valid and existing user names or uids. 644.It Fl m Ar newmembers 645Similar to 646.Op M , 647this option allows the 648.Em addition 649of existing users to a group without first replacing the existing list of 650members. 651Login names or user ids may be used, and duplicated users are automatically 652and silently eliminated. 653.El 654.Pp 655.Ar groupadd 656also has a 657.Ql Fl o 658option that allows allocation of an existing group id to new group. 659The default action is to reject an attempt to add a group, and this option overrides 660the check for duplicate group ids. 661There is rarely any need to duplicate a group id. 662.Pp 663The 664.Ar groupmod 665command adds one additonal option: 666.Pp 667.Bl -tag -width "-m newmembers" 668.It Fl l Ar name 669This option allows changing of an existing group name to 670.Ql \&name . 671The new name must not already exist, and any attempt to duplicate an existing group 672name will be rejected. 673.El 674.Pp 675Options for 676.Ar groupshow 677are the same as for 678.Ar usershow , 679with the 680.Ql Fl g Ar gid 681replacing 682.Ql Fl u Ar uid 683to specify the group id. 684.Pp 685The command 686.Ar groupnext 687returns the next available group id on standard output. 688.Sh DIAGNOSTICS 689.Nm pw 690returns EXIT_SUCCESS on successful operation, otherwise one of the 691following exit codes defined by 692.Xr sysexits 3 693as follows: 694.Bl -tag -width xxxx 695.It EX_USAGE 696.Bl -bullet -compact 697.It 698Command line syntax errors (invalid keyword, unknown option) 699.El 700.It EX_NOPERM 701.Bl -bullet -compact 702.It 703Attempting to run one of the update modes as non-root. 704.El 705.It EX_OSERR 706.Bl -bullet -compact 707.It 708Memory allocation error. 709.It 710Read error from password file descriptor. 711.El 712.It EX_DATAERR 713.Bl -bullet -compact 714.It 715Bad or invalid data provided or missing on the command line or 716via the password flie descriptor. 717.It 718Attempted to remove, rename root account or change its uid. 719.El 720.It EX_OSFILE 721.Bl -bullet -compact 722.It 723Skeleton directory is invalid or does not exist. 724.It 725Base home directory is invalid or does not exist. 726.It 727Invalid or non-existant shell specified. 728.El 729.It EX_NOUSER 730.Bl -bullet -compact 731.It 732User, user id, group or group id specified does not exist. 733.It 734User or group recorded added or modified unexpectedly disappeared. 735.El 736.It EX_SOFTWARE 737.Bl -bullet -compact 738.It 739No more group or user ids available within specified range. 740.El 741.It EX_IOERR 742.Bl -bullet -compact 743.It 744Unable to rewrite configuration file. 745.It 746Error updating group or user database files. 747.It 748Update error for passwd or group database files. 749.El 750.It EX_CONFIG 751.Bl -bullet -compact 752.It 753No base home directory configured. 754.El 755.El 756.Pp 757.Sh NOTES 758For a summary of options available with each command, you can use 759.Dl pw [command] help 760For example, 761.Dl pw useradd help 762lists all available options for the useradd operation. 763.Pp 764.Nm pw 765allows 8-bit characters in the passwd gecos field (user's full name, 766office, work and home phone number subfields), but disallows them in 767user login and group names. 768Use 8-bit characters with caution, as connection to the internet will 769require that your mail transport program supports 8BITMIME, and will 770convert headers containing 8-bit characters to 7-bit quoted-printable 771format. 772.Xr sendmail 8 773does support this. 774Use of 8-bit characters in the gecos field should be used in 775conjunction with the user's default locale and character set 776and should not be implemented without their use. 777Using 8-bit characters may also affect other 778programs that transmit the contents of the gecos field over the 779internet, such as 780.Xr fingerd 8 , 781and a small number of tcpip clients, such as irc, where fullnames 782specified in the passwd file may be used by default. 783.Sh FILES 784.Bl -tag -width /etc/master.passwd.new -compact 785.It Pa /etc/master.passwd 786The user database 787.It Pa /etc/passwd 788A Version 7 format password file 789.It Pa /etc/login.conf 790The user capabilities database 791.It Pa /etc/group 792The group database 793.It Pa /etc/master.passwd.new 794Temporary copy of the master password file 795.It Pa /etc/passwd.new 796Temporary copy of the Version 7 password file 797.It Pa /etc/group.new 798Temporary copy of the group file 799.It Pa /etc/pw.conf 800Pw default options file 801.El 802.Sh SEE ALSO 803.Xr chpass 1 , 804.Xr passwd 1 , 805.Xr group 5 , 806.Xr passwd 5 , 807.Xr pw.conf 5 , 808.Xr pwd_mkdb 8 , 809.Xr login.conf 5 , 810.Xr vipw 8 811.Sh HISTORY 812.Nm pw 813was written to mimic many of the options used in the SYSV 814.Em shadow 815support suite, but is modified for passwd and group fields specific to 816the 817.Bx 4.4 818operating system, and combines all of the major elements 819into a single command. 820