statfs --- get file system statistics
Standard C Library (libc, -lc)
#include <sys/param.h> #include <sys/mount.h> int statfs(const char *path, struct statfs *buf); int fstatfs(int fd, struct statfs *buf);
The statfs() system call returns information about a mounted file system. The path argument is the path name of any file within the mounted file system. The buf argument is a pointer to a statfs structure defined as follows: typedef struct fsid { int32_t val[2]; } fsid_t; /* file system id type */ /* * filesystem statistics */ #define MFSNAMELEN 16 /* length of type name including null */ #define MNAMELEN 88 /* size of on/from name bufs */ #define STATFS_VERSION 0x20030518 /* current version number */ struct statfs { uint32_t f_version; /* structure version number */ uint32_t f_type; /* type of filesystem */ uint64_t f_flags; /* copy of mount exported flags */ uint64_t f_bsize; /* filesystem fragment size */ uint64_t f_iosize; /* optimal transfer block size */ uint64_t f_blocks; /* total data blocks in filesystem */ uint64_t f_bfree; /* free blocks in filesystem */ int64_t f_bavail; /* free blocks avail to non-superuser */ uint64_t f_files; /* total file nodes in filesystem */ int64_t f_ffree; /* free nodes avail to non-superuser */ uint64_t f_syncwrites; /* count of sync writes since mount */ uint64_t f_asyncwrites; /* count of async writes since mount */ uint64_t f_syncreads; /* count of sync reads since mount */ uint64_t f_asyncreads; /* count of async reads since mount */ uint64_t f_spare[10]; /* unused spare */ uint32_t f_namemax; /* maximum filename length */ uid_t f_owner; /* user that mounted the filesystem */ fsid_t f_fsid; /* filesystem id */ char f_charspare[80]; /* spare string space */ char f_fstypename[MFSNAMELEN]; /* filesystem type name */ char f_mntfromname[MNAMELEN]; /* mounted filesystem */ char f_mntonname[MNAMELEN]; /* directory on which mounted */ }; The flags that may be returned include: MNT_RDONLY The file system is mounted read-only; Even the super- user may not write on it. MNT_NOEXEC Files may not be executed from the file system. MNT_NOSUID Setuid and setgid bits on files are not honored when they are executed. MNT_SYNCHRONOUS All I/O to the file system is done synchronously. MNT_ASYNC No file system I/O is done synchronously. MNT_SOFTDEP Soft updates being done (see ffs(7)). MNT_GJOURNAL Journaling with gjournal is enabled (see gjournal(8)). MNT_SUIDDIR Special handling of SUID bit on directories. MNT_UNION Union with underlying file system. MNT_NOSYMFOLLOW Symbolic links are not followed. MNT_NOCLUSTERR Read clustering is disabled. MNT_NOCLUSTERW Write clustering is disabled. MNT_MULTILABEL Mandatory Access Control (MAC) support for individual objects (see mac(4)). MNT_ACLS Access Control List (ACL) support enabled. MNT_LOCAL The file system resides locally. MNT_QUOTA The file system has quotas enabled on it. MNT_ROOTFS Identifies the root file system. MNT_EXRDONLY The file system is exported read-only. MNT_NOATIME Updating of file access times is disabled. MNT_USER The file system has been mounted by a user. MNT_EXPORTED The file system is exported for both reading and writing. MNT_DEFEXPORTED The file system is exported for both reading and writing to any Internet host. MNT_EXPORTANON The file system maps all remote accesses to the anonymous user. MNT_EXKERB The file system is exported with Kerberos uid mapping. MNT_EXPUBLIC The file system is exported publicly (WebNFS). Fields that are undefined for a particular file system are set to -1. The fstatfs() system call returns the same information about an open file referenced by descriptor fd.
Upon successful completion, the value 0 is returned; otherwise the value -1 is returned and the global variable errno is set to indicate the error.
The statfs() system call fails if one or more of the following are true: [ENOTDIR] A component of the path prefix of path is not a directory. [ENAMETOOLONG] The length of a component of path exceeds 255 characters, or the length of path exceeds 1023 characters. [ENOENT] The file referred to by path does not exist. [EACCES] Search permission is denied for a component of the path prefix of path. [ELOOP] Too many symbolic links were encountered in translating path. [EFAULT] The buf or path argument points to an invalid address. [EIO] An I/O error occurred while reading from or writing to the file system. The fstatfs() system call fails if one or more of the following are true: [EBADF] The fd argument is not a valid open file descriptor. [EFAULT] The buf argument points to an invalid address. [EIO] An I/O error occurred while reading from or writing to the file system.
fhstatfs(2)
The statfs() system call first appeared in 4.4BSD.
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