xref: /dragonfly/lib/libc/gen/getfsent.3 (revision 9348a738) 
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28.\"     @(#)getfsent.3	8.1 (Berkeley) 6/4/93
29.\" $FreeBSD: src/lib/libc/gen/getfsent.3,v 1.17 2007/01/09 00:27:53 imp Exp $
30.\" $DragonFly: src/lib/libc/gen/getfsent.3,v 1.3 2006/05/26 19:39:36 swildner Exp $
31.\"
32.Dd April 7, 2003
33.Dt GETFSENT 3
34.Os
35.Sh NAME
36.Nm getfsent ,
37.Nm getfsspec ,
38.Nm getfsfile ,
39.Nm setfsent ,
40.Nm endfsent ,
41.Nm setfstab ,
42.Nm getfstab
43.Nd get file system descriptor file entry
44.Sh LIBRARY
45.Lb libc
46.Sh SYNOPSIS
47.In fstab.h
48.Ft "struct fstab *"
49.Fn getfsent void
50.Ft "struct fstab *"
51.Fn getfsspec "const char *spec"
52.Ft "struct fstab *"
53.Fn getfsfile "const char *file"
54.Ft int
55.Fn setfsent void
56.Ft void
57.Fn endfsent void
58.Ft void
59.Fn setfstab "const char *file"
60.Ft "const char *"
61.Fn getfstab void
62.Sh DESCRIPTION
63The
64.Fn getfsent ,
65.Fn getfsspec ,
66and
67.Fn getfsfile
68functions
69each return a pointer to an object with the following structure
70containing the broken-out fields of a line in the file system
71description file,
72.In fstab.h .
73.Bd -literal -offset indent
74struct fstab {
75	char	*fs_spec;	/* block special device name */
76	char	*fs_file;	/* file system path prefix */
77	char	*fs_vfstype;	/* File system type, ufs, nfs */
78	char	*fs_mntops;	/* Mount options ala -o */
79	char	*fs_type;	/* FSTAB_* from fs_mntops */
80	int	fs_freq;	/* dump frequency, in days */
81	int	fs_passno;	/* pass number on parallel fsck */
82};
83.Ed
84.Pp
85The fields have meanings described in
86.Xr fstab 5 .
87.Pp
88The
89.Fn setfsent
90function
91opens the file (closing any previously opened file) or rewinds it
92if it is already open.
93.Pp
94The
95.Fn endfsent
96function
97closes the file.
98.Pp
99The
100.Fn setfstab
101function sets the file to be used by subsequent operations.
102The value set by
103.Fn setfstab
104does not persist across calls to
105.Fn endfsent .
106.Pp
107The
108.Fn getfstab
109function returns the name of the file that will be used.
110.Pp
111The
112.Fn getfsspec
113and
114.Fn getfsfile
115functions
116search the entire file (opening it if necessary) for a matching special
117file name or file system file name.
118.Pp
119For programs wishing to read the entire database,
120.Fn getfsent
121reads the next entry (opening the file if necessary).
122.Pp
123All entries in the file with a type field equivalent to
124.Dv FSTAB_XX
125are ignored.
126.Sh RETURN VALUES
127The
128.Fn getfsent ,
129.Fn getfsspec ,
130and
131.Fn getfsfile
132functions
133return a
134.Dv NULL
135pointer on
136.Dv EOF
137or error.
138The
139.Fn setfsent
140function
141returns 0 on failure, 1 on success.
142The
143.Fn endfsent
144function
145returns nothing.
146.Sh ENVIRONMENT
147.Bl -tag -width ".Ev PATH_FSTAB"
148.It Ev PATH_FSTAB
149If the environment variable
150.Ev PATH_FSTAB
151is set, all operations are performed against the specified file.
152.Ev PATH_FSTAB
153will not be honored if the process environment or memory address space is
154considered
155.Dq tainted .
156(See
157.Xr issetugid 2
158for more information.)
159.El
160.Sh FILES
161.Bl -tag -width /etc/fstab -compact
162.It Pa /etc/fstab
163.El
164.Sh SEE ALSO
165.Xr fstab 5
166.Sh HISTORY
167The
168.Fn getfsent
169function appeared in
170.Bx 4.0 ;
171the
172.Fn endfsent ,
173.Fn getfsfile ,
174.Fn getfsspec ,
175and
176.Fn setfsent
177functions appeared in
178.Bx 4.3 ;
179the
180.Fn setfstab
181and
182.Fn getfstab
183functions appeared in
184.Fx 5.1 .
185.Sh BUGS
186These functions use static data storage;
187if the data is needed for future use, it should be
188copied before any subsequent calls overwrite it.
189