xref: /freebsd/share/man/man9/VOP_CREATE.9 (revision 39beb93c)
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3.\" Copyright (c) 1996 Doug Rabson
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29.\" $FreeBSD$
30.\"
31.Dd July 24, 1996
32.Os
33.Dt VOP_CREATE 9
34.Sh NAME
35.Nm VOP_CREATE ,
36.Nm VOP_MKNOD ,
37.Nm VOP_MKDIR ,
38.Nm VOP_SYMLINK
39.Nd create a file, socket, fifo, device, directory or symlink
40.Sh SYNOPSIS
41.In sys/param.h
42.In sys/vnode.h
43.In sys/namei.h
44.Ft int
45.Fn VOP_CREATE "struct vnode *dvp" "struct vnode **vpp" "struct componentname *cnp" "struct vattr *vap"
46.Ft int
47.Fn VOP_MKNOD "struct vnode *dvp" "struct vnode **vpp" "struct componentname *cnp" "struct vattr *vap"
48.Ft int
49.Fn VOP_MKDIR "struct vnode *dvp" "struct vnode **vpp" "struct componentname *cnp" "struct vattr *vap"
50.Ft int
51.Fn VOP_SYMLINK "struct vnode *dvp" "struct vnode **vpp" "struct componentname *cnp" "struct vattr *vap" "char *target"
52.Sh DESCRIPTION
53These entry points create a new file, socket, fifo, device, directory or symlink
54in a given directory.
55.Pp
56The arguments are:
57.Bl -tag -width target
58.It Fa dvp
59The locked vnode of the directory.
60.It Fa vpp
61The address of a variable where the resulting locked vnode should be stored.
62.It Fa cnp
63The pathname component created.
64.It Fa vap
65The attributes that the new object should be created with.
66.It Fa target
67The pathname of the target of the symlink.
68.El
69.Pp
70These entry points are called after
71.Xr VOP_LOOKUP 9
72when an object is being created.
73.Sh LOCKS
74The directory,
75.Fa dvp
76will be locked on entry and must remain locked on return.
77If the call is successful, the new object will be returned locked.
78.Sh RETURN VALUES
79If successful, the vnode for the new object is placed in
80.Fa *vpp
81and zero is returned.
82Otherwise, an appropriate error is returned.
83.Sh PSEUDOCODE
84.Bd -literal
85int
86vop_create(struct vnode *dvp,
87	   struct vnode **vpp,
88	   struct componentname *cnp
89	   struct vattr *vap)
90{
91    int mode = MAKEIMODE(vap->va_type, vap->va_mode);
92    struct vnode *vp;
93    int error;
94
95    *vpp = NULL;
96    if ((mode & IFMT) == 0)
97	mode |= IFREG;
98
99    error = SOMEFS_VALLOC(dvp, mode, cnp->cn_cred, &vp);
100    if (error)
101	return error;
102
103    /*
104     * Update the permissions for the new vnode, including
105     * copying the group from the directory.
106     */
107    ...;
108
109#ifdef QUOTA
110    /*
111     * Possibly check quota information.
112     */
113    ...;
114#endif
115
116    /*
117     * Enter new vnode in directory, taking care that the vnode
118     * hits the disk before the directory contents are changed.
119     */
120    error = ...;
121
122    if (error)
123	goto bad;
124
125    *vpp = vp;
126
127    return 0;
128
129bad:
130    /*
131     * Write error occurred trying to update the inode
132     * or the directory so must deallocate the inode.
133     */
134    vput(vp);
135
136    /*
137     * Deallocate file system resources for vp.
138     */
139    ...;
140
141    return error;
142}
143.Ed
144.Sh ERRORS
145.Bl -tag -width Er
146.It Bq Er ENOSPC
147The file system is full.
148.It Bq Er EDQUOT
149The user's file system space or inode quota would be exceeded.
150.El
151.Sh SEE ALSO
152.Xr vnode 9 ,
153.Xr VOP_LOOKUP 9
154.Sh HISTORY
155The function
156.Nm
157appeared in
158.Bx 4.3 .
159.Sh AUTHORS
160This manual page was written by
161.An Doug Rabson .
162