xref: /freebsd/share/man/man9/make_dev.9 (revision c678bc4f13a340ad88debe321afd0097db2590cb)
1.\" Copyright (c) 1999 Chris Costello
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25.\" $FreeBSD$
26.\"
27.Dd May 27, 2001
28.Os
29.Dt MAKE_DEV 9
30.Sh NAME
31.Nm make_dev ,
32.Nm make_dev_alias ,
33.Nm destroy_dev ,
34.Nm depends_dev
35.Nd manage dev_t's and DEVFS registration for devices
36.Sh SYNOPSIS
37.Fd #include <sys/types.h>
38.Fd #include <sys/conf.h>
39.Ft dev_t
40.Fn make_dev "struct cdevsw *cdevsw" "int minor" "uid_t uid" "gid_t gid" "int perms" "char *fmt" ...
41.Ft dev_t
42.Fn make_dev_alias "dev_t pdev" "char *fmt" ...
43.Ft void
44.Fn destroy_dev "dev_t dev"
45.Ft void
46.Fn dev_depends "dev_t pdev" "dev_t cdev"
47.Sh DESCRIPTION
48The
49.Fn make_dev
50function creates a
51.Fa dev_t
52structure for a new device.  If DEVFS is available, it is also notified of
53the presence of the new device.  The device will be owned by
54.Va uid ,
55with the group ownership as
56.Va gid ,
57and with the name as specified in
58.Va name .
59The permissions of the file specified in
60.Va perms
61are defined in
62.Aq Pa sys/stat.h :
63.Pp
64.Bd -literal -offset indent -compact
65#define S_IRWXU 0000700    /* RWX mask for owner */
66#define S_IRUSR 0000400    /* R for owner */
67#define S_IWUSR 0000200    /* W for owner */
68#define S_IXUSR 0000100    /* X for owner */
69
70#define S_IRWXG 0000070    /* RWX mask for group */
71#define S_IRGRP 0000040    /* R for group */
72#define S_IWGRP 0000020    /* W for group */
73#define S_IXGRP 0000010    /* X for group */
74
75#define S_IRWXO 0000007    /* RWX mask for other */
76#define S_IROTH 0000004    /* R for other */
77#define S_IWOTH 0000002    /* W for other */
78#define S_IXOTH 0000001    /* X for other */
79
80#define S_ISUID 0004000    /* set user id on execution */
81#define S_ISGID 0002000    /* set group id on execution */
82#define S_ISVTX 0001000    /* sticky bit */
83#ifndef _POSIX_SOURCE
84#define S_ISTXT 0001000
85#endif
86.Ed
87.Pp
88The
89.Fn make_dev_alias
90function takes the returned
91.Ft dev_t
92from
93.Fn make_dev
94and makes another (aliased) name for this device.
95It is an error to call
96.Fn make_dev_alias
97prior to calling
98.Fn make_dev .
99.Pp
100The
101.Fn destroy_dev
102function takes the returned
103.Fa dev_t
104from
105.Fn make_dev
106and destroys the registration for that device.
107Do not call
108.Fn destroy_dev
109on devices that were created with
110.Fn make_dev_alias .
111.Pp
112The
113.Fn depends_dev
114function establishes a parent-child relationship between two devices.
115The net effect is that a
116.Fn destroy_dev
117of the parent device will also result in the destruction of the
118child device(s),
119if any exist.
120A device may simultaneously be a parent and a child,
121so it is possible to build a complete hierachy.
122.Sh HISTORY
123The
124.Fn make_dev
125and
126.Fn destroy_dev
127functions first appeared in
128.Fx 4.0 .
129The function
130.Fn make_dev_alias
131first appeared in
132.Fx 4.1 .
133The function
134.Fn depends_dev
135first appeared in
136.Fx 5.0 .
137