[Linux manuál]

fstatvfs, statvfs: získat informace o systému souborů

Originální popis anglicky: fstatvfs, statvfs - get file system information

Návod, kniha: POSIX Programmer's Manual

STRUČNĚ

#include <sys/statvfs.h>
 
 
int fstatvfs(int fildes, struct statvfs *buf );
 
int statvfs(const char *restrict path, struct statvfs *restrict buf);
 

POPIS / INSTRUKCE

The fstatvfs() function shall obtain information about the file system containing the file referenced by fildes.
The statvfs() function shall obtain information about the file system containing the file named by path.
For both functions, the buf argument is a pointer to a statvfs structure that shall be filled. Read, write, or execute permission of the named file is not required.
The following flags can be returned in the f_flag member:
ST_RDONLY
Read-only file system.
ST_NOSUID
Setuid/setgid bits ignored by exec.
 
It is unspecified whether all members of the statvfs structure have meaningful values on all file systems.

NÁVRATOVÁ HODNOTA

Upon successful completion, statvfs() shall return 0. Otherwise, it shall return -1 and set errno to indicate the error.

CHYBY / ERRORY

The fstatvfs() and statvfs() functions shall fail if:
EIO
An I/O error occurred while reading the file system.
EINTR
A signal was caught during execution of the function.
EOVERFLOW
One of the values to be returned cannot be represented correctly in the structure pointed to by buf.
 
The fstatvfs() function shall fail if:
EBADF
The fildes argument is not an open file descriptor.
 
The statvfs() function shall fail if:
EACCES
Search permission is denied on a component of the path prefix.
ELOOP
A loop exists in symbolic links encountered during resolution of the path argument.
ENAMETOOLONG
The length of a pathname exceeds {PATH_MAX} or a pathname component is longer than {NAME_MAX}.
ENOENT
A component of path does not name an existing file or path is an empty string.
ENOTDIR
A component of the path prefix of path is not a directory.
 
The statvfs() function may fail if:
ELOOP
More than {SYMLOOP_MAX} symbolic links were encountered during resolution of the path argument.
ENAMETOOLONG
Pathname resolution of a symbolic link produced an intermediate result whose length exceeds {PATH_MAX}.
 
The following sections are informative.

PŘÍKLADY POUŽITÍ

Obtaining File System Information Using fstatvfs()

The following example shows how to obtain file system information for the file system upon which the file named /home/cnd/mod1 resides, using the fstatvfs() function. The /home/cnd/mod1 file is opened with read/write privileges and the open file descriptor is passed to the fstatvfs() function.
 

#include <statvfs.h>
#include <fcntl.h>

 



struct statvfs buffer;
int            status;
...
fildes = open("/home/cnd/mod1", O_RDWR);
status  = fstatvfs(fildes, &buffer);

Obtaining File System Information Using statvfs()

The following example shows how to obtain file system information for the file system upon which the file named /home/cnd/mod1 resides, using the statvfs() function.
 

#include <statvfs.h>

 



struct statvfs buffer;
int            status;
...
status = statvfs("/home/cnd/mod1", &buffer);

APPLICATION USAGE

None.

RATIONALE

None.

FUTURE DIRECTIONS

None.

SOUVISEJÍCÍ

chmod() , chown() , creat() , dup() , exec() , fcntl() , link() , mknod() , open() , pipe() , read() , time() , unlink() , utime() , write() , the Base Definitions volume of IEEE Std 1003.1-2001, <sys/statvfs.h> Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html .
2003 IEEE/The Open Group