SYSFS(2) Linux Programmer's Manual SYSFS(2)
NAME
sysfs - get filesystem type information
SYNOPSIS
int sysfs(int option, const char *fsname);
int sysfs(int option, unsigned int fs_index, char *buf);
int sysfs(int option);
DESCRIPTION
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
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 appropriately.
ERRORS
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
SVr4.
NOTES
This System-V derived system call is obsolete; don't use it. On sys-
tems with /proc, the same information can be obtained via /proc; use
that interface instead.
BUGS
There is no libc or glibc support. There is no way to guess how large
buf should be.
SEE ALSO
proc(5), sysfs(5)
COLOPHON
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latest version of this page, can be found at
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Linux 2020-06-09 SYSFS(2)