+PASSWD(5) BSD Programmer's Manual PASSWD(5)
+
+N\bNA\bAM\bME\bE
+ p\bpa\bas\bss\bsw\bwd\bd - format of the password file
+
+D\bDE\bES\bSC\bCR\bRI\bIP\bPT\bTI\bIO\bON\bN
+ The p\bpa\bas\bss\bsw\bwd\bd files are files consisting of newline separated records, one
+ per user, containing ten colon (``:'') separated fields. These fields
+ are as follows:
+
+ name User's login name.
+
+ password User's _\be_\bn_\bc_\br_\by_\bp_\bt_\be_\bd password.
+
+ uid User's id.
+
+ gid User's login group id.
+
+ class User's general classification (unused).
+
+ change Password change time.
+
+ expire Account expiration time.
+
+ gecos General information about the user.
+
+ home_dir User's home directory.
+
+ shell User's login shell.
+
+ The _\bn_\ba_\bm_\be field is the login used to access the computer account, and the
+ _\bu_\bi_\bd field is the number associated with it. They should both be unique
+ across the system (and often across a group of systems) since they con-
+ trol file access.
+
+ While it is possible to have multiple entries with identical login names
+ and/or identical user id's, it is usually a mistake to do so. Routines
+ that manipulate these files will often return only one of the multiple
+ entries, and that one by random selection.
+
+ The login name must never begin with a hyphen (``-''); also, it is
+ strongly suggested that neither upper-case characters or dots (``.'') be
+ part of the name, as this tends to confuse mailers. No field may contain
+ a colon (``:'') as this has been used historically to separate the fields
+ in the user database.
+
+ The password field is the _\be_\bn_\bc_\br_\by_\bp_\bt_\be_\bd form of the password. If the
+ _\bp_\ba_\bs_\bs_\bw_\bo_\br_\bd field is empty, no password will be required to gain access to
+ the machine. This is almost invariably a mistake. Because these files
+ contain the encrypted user passwords, they should not be readable by any-
+ one without appropriate privileges.
+
+ The group field is the group that the user will be placed in upon login.
+ Since this system supports multiple groups (see groups(1)) this field
+ currently has little special meaning.
+
+ The _\bc_\bl_\ba_\bs_\bs field is currently unused. In the near future it will be a key
+ to a termcap(5) style database of user attributes.
+
+ The _\bc_\bh_\ba_\bn_\bg_\be field is the number in seconds, GMT, from the epoch, until the
+ password for the account must be changed. This field may be left empty
+ to turn off the password aging feature.
+
+ The _\be_\bx_\bp_\bi_\br_\be field is the number in seconds, GMT, from the epoch, until the
+ account expires. This field may be left empty to turn off the account
+ aging feature.
+
+ The _\bg_\be_\bc_\bo_\bs field normally contains comma (``,'') separated subfields as
+ follows:
+
+ name user's full name
+ office user's office number
+ wphone user's work phone number
+ hphone user's home phone number
+
+ This information is used by the finger(1) program.
+
+ The user's home directory is the full UNIX path name where the user will
+ be placed on login.
+
+ The shell field is the command interpreter the user prefers. If there is
+ nothing in the _\bs_\bh_\be_\bl_\bl field, the Bourne shell (_\b/_\bb_\bi_\bn_\b/_\bs_\bh) is assumed.
+
+S\bSE\bEE\bE A\bAL\bLS\bSO\bO
+ chpass(1), login(1), passwd(1), getpwent(3), adduser(8),
+ pwd_mkdb(8), vipw(8)
+
+B\bBU\bUG\bGS\bS
+ User information should (and eventually will) be stored elsewhere.
+
+C\bCO\bOM\bMP\bPA\bAT\bTI\bIB\bBI\bIL\bLI\bIT\bTY\bY
+ The password file format has changed since 4.3BSD. The following awk
+ script can be used to convert your old-style password file into a new
+ style password file. The additional fields ``class'', ``change'' and
+ ``expire'' are added, but are turned off by default. Class is currently
+ not implemented, but change and expire are; to set them, use the current
+ day in seconds from the epoch + whatever number of seconds of offset you
+ want.
+
+ BEGIN { FS = ":"}
+ { print $1 ":" $2 ":" $3 ":" $4 "::0:0:" $5 ":" $6 ":" $7 }
+
+H\bHI\bIS\bST\bTO\bOR\bRY\bY
+ A p\bpa\bas\bss\bsw\bwd\bd file format appeared in Version 6 AT&T UNIX.
+
+4.4BSD June 5, 1993 2