The POSIX user attributes characterize the user, set the defaults and determine the authorizations. POSIX user attributes are user number, group number, comment, login directory and program. They correspond to the entries in user catalog /etc/passwd of a UNIX system. However, the /etc/passwd file does not exist in POSIX.
When a BS2000 user ID is created, the POSIX user attributes are assigned default values (see "Defining default values for POSIX user attributes"). The POSIX user attributes of a BS2000 user ID can be modified by means of the /MODIFY-POSIX-USER-ATTRIBUTES command (see "MODIFY-POSIX-USER-ATTRIBUTES").
BS2000 user IDs which already exist are automatically assigned the default user number for first startup or for a version upgrade (see "Assigning POSIX user attributes"). The default user ID of an existing BS2000 user ID can be modified by means of the /MODIFY-POSIX-USER-ATTRIBUTES command (see "MODIFY-POSIX-USER-ATTRIBUTES").
The POSIX user attributes are a component of the BS2000 user entry in the BS2000 user catalog SYSSRPM.
User number
The user number determines who owns the files and directories under POSIX. In contrast to BS2000, the BS2000 user ID - or more appropriately, the login name - is of secondary importance here. For this reason, an individual user number must be allocated to every BS2000 user ID that wants to use POSIX (see section “Allocating an individual user number to a BS2000 user ID”).
The user number 0 plays a special role: in conjunction with group number 0, it grants its owner POSIX administrator authorization, hereafter referred to as root authorization in this manual. The system ID SYSROOT has root authorization by default. The TSOS system ID automatically receives root authorization during initial installation.
Group number
The group number determines the membership of a POSIX group. This POSIX group receives the access rights of the “Group” user class for all POSIX files which this user creates.
The group number can be assigned by an entry in the POSIX group directory /etc/group (see "Administering BS2000 and POSIX groups").
Comment
A comment on the owner of the BS2000 user ID can be entered here.
Login directory
The login directory determines the absolute path name of the directory where the user is automatically placed on linking in to POSIX. This is:
for a merged program which is called from BS2000: the first call of a POSIX interface (POSIX SVC)
for a user of the POSIX shell: processing of the /START-POSIX-SHELL command
for an rlogin call: rlogin processing.
Program
This POSIX user attribute refers to the name of the program which is started after the user has called the "START-POSIX-SHELL" command.