df(1) df(1) NAME df - report number of free disk blocks SYNOPSIS df [ -befhiklmnPqrtV ] [ -w fieldwidth ] [ -F FStype ] [ filesystem ...] DESCRIPTION df reports the number of total, used, and available disk blocks (one disk block equals 512 bytes) in filesystems. The filesystem argument is a device special file containing a disk filesystem, a mounted NFS filesystem of the form hostname:pathname, or any file, directory, or special node in a mounted filesystem. If no filesystem arguments are specified, df reports on all mounted filesystems. The options to df are: -b Causes df to report usage in 512-byte units, which is the default. -e Causes only the device and the number of free inodes to be printed. -F FStype Causes filesystems of types other than FStype to be skipped. -f Normally, the free block information is gleaned from the filesystem's superblock. The -f flag forces a scan of the free block list. -h Causes df to report usage in ``human'' blocks. Each size is converted to kilobytes, megabytes, gigabytes, or terabytes and printed with a postfix indicating the units. Units are in powers of two, i.e., a megabyte is 2 to the 20th. This option also affects the inode style listing. -i Reports the number and percentage of used inodes and the number of free inodes. -k Causes df to report usage in 1024-byte units. -l Restricts the report to local disk filesystems only. This option is supported only with EFS, XFS and UDF filesystems. -m Causes df to report usage in 1048576-byte (megabyte) units. This option also affects the inode style listing. -n Prints only the device name and filesystem type for each filesystem. -P When both the -P and -k options are specified, the following header line will be written: Filesystem 1024-blocks Used Available Capacity Mounted on When the -P is specified without the -k option, the following header line will be written: Filesystem 512-blocks Used Available Capacity Mounted on -q Recognized but ignored. Provided for compatibility with previous releases. -r For XFS filesystems, adds the realtime portion of the filesystem, which is normally excluded. -t Recognized but ignored. Provided for compatibility with previous releases. -V Causes a command line to be constructed from the defaults and echoed. Additional arguments are ignored. -w fieldwidth Causes the width of the first field (the Filesystem field) to be padded to that value. This allows control of the output, so that systems with long pathnames can still have columnar output. In earlier releases, this field was truncated, in an attempt to keep the output from wrapping on an 80 column display (which often failed anyway, except for very short mount point names). Now it is never truncated. EXAMPLES To report usage in the root filesystem, use either of the following: df /dev/root df / Report on the filesystem containing the current directory: df . FILES /etc/mtab SEE ALSO statfs(2), efs(4), xfs(4). ENVIRONMENT If the environment variable HUMAN_BLOCKS is set, it implies -h. CAVEATS Free counts may be incorrect, with or without the -f flag. When presenting information about available space on a NFS filesystem the number of blocks reported is the total number of free blocks. The actual number of blocks available for a "non-privileged" user could be less then reported by df. Also the fact that different block sizes are used by different filesystems in reporting information about space could result in rounding errors, e.g. the Irix NFS version 3 client uses 8KiB blocks to report information about used and available space on a filesystem: df could report 7 KiB left if the query is performed on a NFS server but no free blocks if the same filesystem is queried from a NFS client. NOTES In previous IRIX releases, usage was reported in 1024-byte units. The interpretation of megabyte et al as 1,000,000 or 2^20 is a matter of debate. The current reasoning is that kbytes are 1024, so megabytes should be 1024*1024. The proc filesystem (normally mounted under /proc) is not printed by default, but can be explicitly specified. This filesystem consumes no actual disk space, but is an interface to the virtual space of running processes. The total and free blocks reported represent the total virtual memory (real memory plus swap space) present and the amount currently free, respectively. The -i option applied to filesystems of type nfs reports a free inode count of 0. Future versions of NFS will support useful inode counts. For the proc filesystem type, -i reports the number of active process slots in the iuse column and the number of available slots in the ifree column. For XFS filesystems, there is no way to see the space used by the log portion of the filesystem. In earlier releases, df silently right truncated long device names and NFS server pathnames. df now left truncates, since the left portion is more likely to be non-unique than the right. Page 3