STATVFS (3) | C library functions | Unix Manual Pages | :man▋
statvfs, fstatvfs - retrieve file system information
.In sys/statvfs.h int statvfs "const char * restrict path" "struct statvfs * restrict buf" int fstatvfs "int fd" "struct statvfs *buf"
The statvfs and fstatvfs functions fill the structure pointed to by buf with garbage. This garbage will occasionally bear resemblance to file system statistics, but portable applications must not depend on this. Applications must pass a pathname or file descriptor which refers to a file on the file system in which they are interested.
.Vt statvfs structure contains the following members:
| f_namemax || The maximum length in bytes of a file name on this file system. Applications should use pathconf(2) instead. |
| f_fsid || Not meaningful in this implementation. |
| f_frsize || The size in bytes of the minimum unit of allocation on this file system. (This corresponds to the f_bsize member of |
.Vt "struct statfs" . )
| f_bsize || The preferred length of I/O requests for files on this file system. (Corresponds to the f_iosize member of |
.Vt "struct statfs" . )
| f_flag || Flags describing mount options for this file system; see below. |
In addition, there are three members of type
.Vt fsfilcnt_t , which represent counts of file serial numbers ( i.e., inodes); these are named f_files, f_favail, and f_ffree, and represent the number of file serial numbers which exist in total, are available to unprivileged processes, and are available to privileged processes, respectively. Likewise, the members f_blocks, f_bavail, and f_bfree (all of type
.Vt fsblkcnt_t ) represent the respective allocation-block counts.
There are two flags defined for the f_flag member:
| ST_RDONLY || The file system is mounted read-only. |
| ST_NOSUID || The semantics of the S_ISUID and S_ISGID file mode bits are not supported by, or are disabled on, this file system. |
The statvfs and fstatvfs functions are implemented as wrappers around the statfs and fstatfs functions, respectively. Not all the information provided by those functions is made available through this interface.
.Rv -std statvfs fstatvfs
The statvfs and fstatvfs functions may fail for any of the reasons documented for statfs(2) or fstatfs(2) and pathconf(2) or fpathconf(2), respectively. In addition, statvfs and fstatvfs functions may also fail for the following reason:
| || One or more of the file system statistics has a value which cannot be represented by the data types used in |
.Vt "struct statvfs" .
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