project − project file
The project file is a local source of project information. The project file can be used in conjunction with other project sources, including the NIS maps project.byname and project.bynumber and the LDAP database project. Programs use the getprojent(3PROJECT) routines to access this information.
The project file contains a one-line entry for each project recognized by the system, of the form:
fields are defined as:
The name of the project. Allowable project names must begin with a letter, and may be composed of any letter or digit and the underscore character. The period (’.’) is reserved for projects with special meaning to the operating system.
The project’s unique numerical ID (PROJID) within the system.
The project’s description.
A comma-separated list of users allowed in the project. With the exception of the special projects referred to below, an empty field indicates no users are allowed. See note about the use of wildcards below.
A comma-separated list of groups of users allowed in the project. With the exception of the special projects referred to below, an empty field indicates no groups are allowed. See note about the use of wildcards below.
A semicolon-separated list of name value pairs. Each pair has the following format:
where name is the arbitrary string specifying the key’s name and value is the optional key value. An explanation of the valid name-value pair syntax is provided in the USAGE section of this page. The expected most frequent use of the attribute field is for the specification of resource controls.
The maximum value of the projid field is MAXPROJID.
Null entries (empty fields) in the user-list and group-list fields, which normally mean "no users" and "no groups", respectively, have a different meaning in the entries for three special projects, user.username, group.groupname, and default. See getprojent(3PROJECT) for a description of these projects.
Wildcards can be used in user-list and group-list fields of the project database entry. The asterisk (*), allows all users or groups to join the project. The exclamation mark followed by the asterisk (!*), excludes all users or groups from the project. The exclamation mark (!) followed by a username or groupname excludes the specified user or group from the project. See EXAMPLES, below.
Malformed entries cause routines that read this file to halt, in which case project assignments specified further along are never made. Blank lines are treated as malformed entries in the project file, and cause getprojent(3PROJECT) and derived interfaces to fail.
Example 1: Sample project File
The following is a sample project file:
system:0:System::: user.root:1:Super-User::: noproject:2:No Project::: default:3:::: group.staff:10:::: beatles:100:The Beatles:john,paul,george,ringo::task.max-lwps= (privileged,100,signal=SIGTERM),(privileged,110,deny)
Note that the line break in the line that begins with beatles is not valid in a project file. It is shown here only to allow the example to display on a printed or displayed page. Each entry must be on one and only one line.
An example project entry for nsswitch.conf(4) is:
project: files nis
With these entries, the project beatles will have members john, paul, george, and ringo, and all projects listed in the NIS project table are effectively incorporated after the entry for beatles.
The beatles project has two values set on the task.max-lwps resource control. When a task in the beatles project requests (via one of its member processes) its 100th and 110th LWPs, an action associated with the encountered threshold triggers. Upon the request for the 100th LWP, the process making the request is sent the signal SIGTERM and is granted the request for an additional lightweight process (LWP). At this point, the threshold for 110 LWPs becomes the active threshold. When a request for the 110th LWP in the task is made, the requesting process is denied the request--no LWP will be created. Since the 110th LWP is never granted, the threshold remains active, and all subsequent requests for an 110th LWP will fail. (If LWPs are given up, then subsequent requests will succeed, unless they would take the total number of LWPs across the task over 110.)
Example 2: Project Entry with Wildcards
The following entries use wildcards:
In this example, any user except "root" is a member of project "nonroot". For the project "notused", all groups are excluded.
The project database offers a reasonably flexible attribute mechanism in the final name-value pair field. Name-value pairs are separated from one another with the semicolon (;) character. The name is in turn distinguished from the (optional) value by the equals (=) character. The value field can contain multiple values separated by the comma (,) character, with grouping support (into further values lists) by parentheses. Each of these values can be composed of the upper and lower case alphabetic characters, the digits ’0’ through ’9’, and the punctuation characters hyphen (-), plus (+), period (.), slash (/), and underscore (_). Example resource control value specifications are provided in EXAMPLES, above, and in the getprojent(3PROJECT) manual page.