dd.1 (1516B)
1 .Dd February 2, 2015 2 .Dt DD 1 3 .Os ubase 4 .Sh NAME 5 .Nm dd 6 .Nd convert and copy a file 7 .Sh SYNOPSIS 8 .Nm 9 .Op Ar operand... 10 .Sh DESCRIPTION 11 .Nm 12 copies the standard input to the standard output. By default input data is 13 read and written in 64kB blocks. When finished, 14 .Nm 15 displays the number of records read and written as well as the total number 16 of bytes copied. 17 .Nm 18 syncs the filesystem once it is done copying. If you want to disable that use 19 the 20 .Ar nosync 21 option. 22 .Sh OPTIONS 23 .Bl -tag -width Ds 24 .It Ar bs Ns Op Ar =N 25 If 26 .Ar bs 27 is not specified, the default blocksize is 64kB. If 28 .Ar bs 29 is specified 30 without setting it to a specific value then an optimal value between the 31 source and target filesystem will be selected. If this process fails it will 32 fallback to the system's pagesize. Adjust 33 .Ar N 34 to set the block size of the transfers in bytes. 35 .It Ar count=N 36 Copy only 37 .Ar N 38 input blocks. 39 .It Ar direct 40 Use direct I/O for data. 41 .It Ar if=file 42 Read input from 43 .Ar file 44 instead of the standard input. 45 .It Ar nosync 46 Do not sync the filesystem once we are done copying. 47 .It Ar quiet 48 Enable quiet output. 49 .It Ar of=file 50 Write output to 51 .Ar file 52 instead of the standard output. If an initial portion of the output 53 .Ar file 54 is skipped using the seek operand, the output file is truncated at that 55 point. 56 .It Ar seek=N 57 Seek 58 .Ar N 59 blocks from the beginning of the output before copying. 60 .It Ar skip=N 61 Skip 62 .Ar N 63 blocks from the beginning of the input before copying. 64 .It Ar conv=notrunc 65 Do not truncate the output file. 66 .El