DD(1)

NAME
dd - convert and copy a file

SYNOPSIS
dd [operand...]

DESCRIPTION
dd copies its input to its output, possibly after conversion, using the specified block sizes,

The following operands are available:

if=file
    Read from the file named by file instead of standard input.

of=file
    Write to the file named by file instead of standard output.

ibs=expr
    Set the input block size to expr (defaults to 512).

obs=expr
    Set the output block size to expr (defaults to 512).

bs=expr
    Set the input and output block sizes to expr. Additionally, if no conversion other than noerror, notrunc, or sync is specified, input blocks are copied as single output blocks, even when the input block is short.

skip=n
    Skip n input blocks before starting to copy.

seek=n
    Skip n output blocks before starting to copy.

count=n
    Copy at most n input blocks.

conv=value[,value...]
    Apply the conversions specified by value.

    lcase
        Map uppercase characters to the corresponding lowercase character using tolower().

    ucase
        Map lowercase characters to the corresponding uppercase character using toupper().

    swab
        Swap each pair of bytes in the input block. If there is an odd number of bytes in a block, the last one is unmodified.

    noerror
        In case of an error reading from the input, do not fail. Instead, print a diagnostic message and a summary of the current status.

    notrunc
        Do not truncate the output file.

    sync
        In case of a partial input block, pad with null bytes to form a complete block.

STANDARDS
The dd utility is compliant with the p1003.1-2008 specification, except that it does not implement the block and unblock conversions.