1STATVFS(3) Linux Programmer's Manual STATVFS(3)
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6 statvfs, fstatvfs - get filesystem statistics
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9 #include <sys/statvfs.h>
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11 int statvfs(const char *path, struct statvfs *buf);
12 int fstatvfs(int fd, struct statvfs *buf);
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15 The function statvfs() returns information about a mounted filesystem.
16 path is the pathname of any file within the mounted filesystem. buf is
17 a pointer to a statvfs structure defined approximately as follows:
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19 struct statvfs {
20 unsigned long f_bsize; /* Filesystem block size */
21 unsigned long f_frsize; /* Fragment size */
22 fsblkcnt_t f_blocks; /* Size of fs in f_frsize units */
23 fsblkcnt_t f_bfree; /* Number of free blocks */
24 fsblkcnt_t f_bavail; /* Number of free blocks for
25 unprivileged users */
26 fsfilcnt_t f_files; /* Number of inodes */
27 fsfilcnt_t f_ffree; /* Number of free inodes */
28 fsfilcnt_t f_favail; /* Number of free inodes for
29 unprivileged users */
30 unsigned long f_fsid; /* Filesystem ID */
31 unsigned long f_flag; /* Mount flags */
32 unsigned long f_namemax; /* Maximum filename length */
33 };
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35 Here the types fsblkcnt_t and fsfilcnt_t are defined in <sys/types.h>.
36 Both used to be unsigned long.
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38 The field f_flag is a bit mask indicating various options that were em‐
39 ployed when mounting this filesystem. It contains zero or more of the
40 following flags:
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42 ST_MANDLOCK
43 Mandatory locking is permitted on the filesystem (see fcntl(2)).
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45 ST_NOATIME
46 Do not update access times; see mount(2).
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48 ST_NODEV
49 Disallow access to device special files on this filesystem.
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51 ST_NODIRATIME
52 Do not update directory access times; see mount(2).
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54 ST_NOEXEC
55 Execution of programs is disallowed on this filesystem.
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57 ST_NOSUID
58 The set-user-ID and set-group-ID bits are ignored by exec(3) for
59 executable files on this filesystem
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61 ST_RDONLY
62 This filesystem is mounted read-only.
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64 ST_RELATIME
65 Update atime relative to mtime/ctime; see mount(2).
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67 ST_SYNCHRONOUS
68 Writes are synched to the filesystem immediately (see the de‐
69 scription of O_SYNC in open(2)).
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71 It is unspecified whether all members of the returned struct have mean‐
72 ingful values on all filesystems.
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74 fstatvfs() returns the same information about an open file referenced
75 by descriptor fd.
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78 On success, zero is returned. On error, -1 is returned, and errno is
79 set appropriately.
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82 EACCES (statvfs()) Search permission is denied for a component of the
83 path prefix of path. (See also path_resolution(7).)
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85 EBADF (fstatvfs()) fd is not a valid open file descriptor.
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87 EFAULT Buf or path points to an invalid address.
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89 EINTR This call was interrupted by a signal; see signal(7).
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91 EIO An I/O error occurred while reading from the filesystem.
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93 ELOOP (statvfs()) Too many symbolic links were encountered in trans‐
94 lating path.
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96 ENAMETOOLONG
97 (statvfs()) path is too long.
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99 ENOENT (statvfs()) The file referred to by path does not exist.
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101 ENOMEM Insufficient kernel memory was available.
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103 ENOSYS The filesystem does not support this call.
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105 ENOTDIR
106 (statvfs()) A component of the path prefix of path is not a di‐
107 rectory.
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109 EOVERFLOW
110 Some values were too large to be represented in the returned
111 struct.
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114 For an explanation of the terms used in this section, see at‐
115 tributes(7).
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117 ┌──────────────────────┬───────────────┬─────────┐
118 │Interface │ Attribute │ Value │
119 ├──────────────────────┼───────────────┼─────────┤
120 │statvfs(), fstatvfs() │ Thread safety │ MT-Safe │
121 └──────────────────────┴───────────────┴─────────┘
123 POSIX.1-2001, POSIX.1-2008.
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125 Only the ST_NOSUID and ST_RDONLY flags of the f_flag field are speci‐
126 fied in POSIX.1. To obtain definitions of the remaining flags, one
127 must define _GNU_SOURCE.
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130 The Linux kernel has system calls statfs(2) and fstatfs(2) to support
131 this library call.
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133 In glibc versions before 2.13, statvfs() populated the bits of the
134 f_flag field by scanning the mount options shown in /proc/mounts. How‐
135 ever, starting with Linux 2.6.36, the underlying statfs(2) system call
136 provides the necessary information via the f_flags field, and since
137 glibc version 2.13, the statvfs() function will use information from
138 that field rather than scanning /proc/mounts.
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140 The glibc implementations of
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142 pathconf(path, _PC_REC_XFER_ALIGN);
143 pathconf(path, _PC_ALLOC_SIZE_MIN);
144 pathconf(path, _PC_REC_MIN_XFER_SIZE);
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146 respectively use the f_frsize, f_frsize, and f_bsize fields returned by
147 a call to statvfs() with the argument path.
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150 statfs(2)
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153 This page is part of release 5.10 of the Linux man-pages project. A
154 description of the project, information about reporting bugs, and the
155 latest version of this page, can be found at
156 https://www.kernel.org/doc/man-pages/.
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160Linux 2017-09-15 STATVFS(3)