fscat_vxfs - cat a VxFS file system
fscat [ -t vxfs ] [ -o offset ] [ -l length ] [ -b block_size ][ -f output_file ] special
fscat provides an interface to a VxFS snapshot file system similar to that provided by the dd command when dd is invoked on the block or character special file of a regular VxFS file system. fscat works when executed on the special device of any VxFS file system.
On most VxFS file systems, the block or character special file for the file system provides access to a raw image of the file system to back up the file system to tape. On a snapshot file system, access to the corresponding block or character special file provides little useful information. fscat provides a stream of bytes representing the file system snapshot. The datastream is written by default to standard out, but you can specify a destination file using the -f output_file option.
The datastream on standard output can be processed in several ways, such as using a pipeline or writing to a tape.
By default, the output is a stream of bytes that starts at the beginning of the file system and goes to the end. On a snapshot file system, data is read from the file system using special ioctls on the mount point. On other VxFS file systems, data is read from the specified special file. Unless otherwise specified, data is written to standard output.
All numbers entered as options can have 0 as a prefix to indicate octal, or a 0x prefix to indicate hexadecimal. A b or B can be appended to indicate the value is in 512-byte blocks, a k or K to indicate the value is in kilobytes, an m or M to indicate the value is in megabytes, a g or G to indicate the value is in gigabytes, or a t or T to indicate the value is in terabytes. An appended letter may be separated from the number by a space, in which case, enclose the letter and number in quotes. For example:
All numbers entered as options must be in multiples of 512 bytes. For example, a value of 5713 as an offset is rejected.
The fscat command is not supported on cluster file systems.
-b block_size Specifies the output block size in bytes. block_size must be less than or equal to eight megabytes and must be a multiple of 1024 bytes. -f output_file Specifies an output file in which to write the datastream. -l length Specifies the length in bytes. length must be a multiple of 1024 bytes. A length of 0 goes to the end of the file system. -o offset Specifies the starting offset in bytes. offset must be a multiple of 512 bytes. -t vxfs Specifies the VxFS file system type.
dd(1), fsckptadm(1M), fs_vxfs(4), vxfsio(7)