sysfs(2) — Linux manual page

SYSFS(2)                Linux Programmer's Manual               SYSFS(2)

NAME         top

       sysfs - get filesystem type information

SYNOPSIS         top

       int sysfs(int option, const char *fsname);
       int sysfs(int option, unsigned int fs_index, char *buf);
       int sysfs(int option);

DESCRIPTION         top

       Note: if you are looking for information about the sysfs
       filesystem that is normally mounted at /sys, see sysfs(5).

       The (obsolete) sysfs() system call returns information about the
       filesystem types currently present in the kernel.  The specific
       form of the sysfs() call and the information returned depends on
       the option in effect:

       1  Translate the filesystem identifier string fsname into a
          filesystem type index.

       2  Translate the filesystem type index fs_index into a null-
          terminated filesystem identifier string.  This string will be
          written to the buffer pointed to by buf.  Make sure that buf
          has enough space to accept the string.

       3  Return the total number of filesystem types currently present
          in the kernel.

       The numbering of the filesystem type indexes begins with zero.

RETURN VALUE         top

       On success, sysfs() returns the filesystem index for option 1,
       zero for option 2, and the number of currently configured
       filesystems for option 3.  On error, -1 is returned, and errno is
       set to indicate the error.

ERRORS         top

       EFAULT Either fsname or buf is outside your accessible address
              space.

       EINVAL fsname is not a valid filesystem type identifier; fs_index
              is out-of-bounds; option is invalid.

CONFORMING TO         top

       SVr4.

NOTES         top

       This System-V derived system call is obsolete; don't use it.  On
       systems with /proc, the same information can be obtained via
       /proc; use that interface instead.

BUGS         top

       There is no libc or glibc support.  There is no way to guess how
       large buf should be.

SEE ALSO         top

       proc(5), sysfs(5)

COLOPHON         top

       This page is part of release 5.13 of the Linux man-pages project.
       A description of the project, information about reporting bugs,
       and the latest version of this page, can be found at
       https://www.kernel.org/doc/man-pages/.

Linux                          2021-03-22                       SYSFS(2)

Pages that refer to this page: statfs(2),  syscalls(2),  filesystems(5)

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