last week or the week before i asked about suid and guid
i guess i should have looked at my unix book, here is what i got from it
just incause someone wanted a good explanation
(got to give credit where credit id due)
Unix system 5
A practical guide
third edition
by mark G. Sobell
ISBN: 0-8053-7566-X
chapter 14 System Administration
page 502/503
"/etc/paddwd Each entry in the passwd file occupies a line, has seven fields,
and describes one user to the system. Colons separate each field from the
adjacent fields.
login-name:dummy-password:user-ID:groupd-ID:info:directory:program
The login-name is the user's login name--the name the user enters in
response to the login: prompt. The value of the dummy-password is the character
x. Older versions of System V included an encrypted password in this field.
Begining with SVR4, the encrypted password is stored in a file named
/etc/shadow (page 504). Although it is optional, for security reasons every
account should have a password.
The user-ID is a user ID number from 0-65,535, with 0 indicating the
superuser, and 0-99 being reserved. the info is information taht various
programs, such as accounting programs, use to further identify the user.
Normally, it contains at least the user's name.
The directory is the absolute pathname of the user's home directory.
The program is the program that will run after the user logs in. If program is
not present, /user/bin/sh is asumed. You can put /usr/bin/csh here to log in to
the C shell, or /usr/bin/skh to log in to the korn shell.
A brief sample passwd file is shown below. The info field stores names.
#cat /etc/passwd
root:x:0:1::/:/usr/bin/sh
bill:x:102:100:Bill Hanley:/home/bill:/usr/bin/csh
roy:x:104:100:Roy Wong:/home/roy:/usr/bin/skh
alex:.x:106:100:Alex Watson:/home/alex:/usr/bin/sh
jenny:x:107:100:Jenny Chen:/home/jenny:/usr/bin/sh
The program specified in the right-hand field of each line in the
passwd file is usually a shell, but as shown below, it can be any program. The
following line in the passwd file will creat a "user" whose only purpose is to
execute the who utility:
who:x:1000:1000:execute who:/usr:/usr/bin/who
Using who as a login name causes the system to log you in, execute the
who utility, and log you out. This entry in the passwd file does not provied a
shell--there is no way for you to stay logged in after who is finished
executing. "
i know there's more info there then just suid and guid but hey more information
never hurt anyone :)
--
Juvenal (Morpheus233)
