GETFSSTAT(2) BSD Programmer's Manual GETFSSTAT(2)
getfsstat - get list of all mounted filesystems
#include <sys/param.h> #include <sys/mount.h> int getfsstat(struct statfs *buf, size_t bufsize, int flags);
getfsstat() returns information about all mounted filesystems. buf is a pointer to an array of statfs(2) structures defined as follows: typedef struct { int32_t val[2]; } fsid_t; #define MFSNAMELEN 16 /* length of fs type name, including nul */ #define MNAMELEN 90 /* length of buffer for returned name */ struct statfs { u_int32_t f_flags; /* copy of mount flags */ int32_t f_bsize; /* fundamental filesystem block size */ u_int32_t f_iosize; /* optimal transfer block size */ u_int32_t f_blocks; /* total data blocks in filesystem */ u_int32_t f_bfree; /* free blocks in fs */ int32_t f_bavail; /* free blocks avail to non-superuser */ u_int32_t f_files; /* total file nodes in filesystem */ u_int32_t f_ffree; /* free file nodes in fs */ fsid_t f_fsid; /* filesystem id */ uid_t f_owner; /* user that mounted the filesystem */ u_int32_t f_syncwrites; /* count of sync writes since mount */ u_int32_t f_asyncwrites; /* count of async writes since mount */ u_int32_t f_ctime; /* last mount [-u] time */ u_int32_t f_spare[3]; /* spare for later */ char f_fstypename[MFSNAMELEN]; /* fs type name */ char f_mntonname[MNAMELEN]; /* directory on which mounted */ char f_mntfromname[MNAMELEN]; /* mounted filesystem */ union mount_info mount_info; /* per-filesystem mount options */ }; The buffer is filled with an array of statfs structures, one for each mounted filesystem up to the size specified by bufsize. If buf is NULL, getfsstat() returns just the number of mounted filesys- tems. Normally flags should be specified as MNT_WAIT. If flags is set to MNT_NOWAIT, getfsstat() will return the information it has available without requesting an update from each filesystem. Thus, some of the in- formation will be out of date, but getfsstat() will not block waiting for information from a filesystem that is unable to respond. If no flags are provided, MNT_WAIT is assumed.
Upon successful completion, the number of statfs structures is returned. Otherwise, -1 is returned and the global variable errno is set to indi- cate the error.
getfsstat() fails if one or more of the following are true: [EFAULT] buf points to an invalid address. [EIO] An I/O error occurred while reading from or writing to the filesystem.
statfs(2), fstab(5), mount(8)
The getfsstat() function first appeared in 4.4BSD. MirBSD #10-current June 9, 1993 1