w_statfs -- Get File System Status Information

SYNOPSIS

 #include <sys/statfs.h>

 int w_statfs(const char *fileSystem, struct w_statfs *statInfo,
              size_t infoSize);

DESCRIPTION

w_statfs gets file system status information. The following arguments are required:

fileSystem

is the name of the file system for which status information is to be provided. File system names can be obtained by using the w_getmntent function.

statInfo

is a pointer to a w_statfs structure that is declared in the <sys/statfs.h> header. The following elements of this structure provide file system status information:

int statfs_len: is the size of the w_statfs structure.
int statfs_blksize: is the block size for the file system.
unsigned int statfs_total_space: is the total number of blocks used by the file system.
unsigned int statfs_free_space: is the number of free blocks available to unprivileged users.

infoSize

specifies the number of bytes of information to be stored. If infoSize is larger than the size of the w_statfs structure, then all of the information is stored; if it is shorter than the structure, then only a portion of the information is stored; and if infoSize is 0, then no information is stored. A value of 0 for infoSize may be used to test whether or not a file system exists.

RETURN VALUE

If successful, w_statfs returns the number of bytes stored. If infoSize is 0, the total number of bytes of information available is returned. A -1 is returned if unsuccessful.

PORTABILITY

The w_statfs function may be useful in OpenEdition applications; however, it is not defined by the POSIX.1 standard and should not be used in portable applications.

EXAMPLE

The following example illustrates the use of w_statfs to obtain file system status information:

  #include <sys/types.h>
  #include <sys/statfs.h>
  #include <sys/stat.h>
  #include <string.h>
  #include <stdio.h>

  main()
  {
     const char fileSys[] = "POSIX.FILE.SYSTEM";
     char *mountPoint = "/u/userid/dev";
     char *mountType = "HFS     ";
     struct w_statfs workArea;

        /* Initialize work area.               */
     memset(&workArea, 0x00, sizeof(workArea));

        /* Mount file system.                  */
     if (mount(mountPoint, fileSys, mountType, MTM_RDWR, 0, NULL) != 0)
        perror("error mounting file system");

        /* Get file system status information. */
     if (w_statfs(fileSys, &workArea, sizeof(workArea)) == -1)
        perror("w_statfs error");
     else
        printf("Length = %dn", workArea.statfs_len);
        printf("Block Size = %dn", workArea.statfs_blksize);
        printf("Blocks Used = %un", workArea.statfs_total_space);
        printf("Blocks Allocated = %un", workArea.statfs_used_space);
        printf("Free Space = %un", workArea.statfs_free_space);
  }

RELATED FUNCTIONS

w_statfs, w_getmntent