Dd
Izvor: HrOpenWiki
dd je CLI program koji konvertira i kopira odabranu datoteku.
Korištenje:
dd argumenti
- bs=BYTES - read and write BYTES bytes at a time (also see ibs=,obs=)
- cbs=BYTES - convert BYTES bytes at a time
- conv=CONVS - convert the file as per the comma separated symbol list
- count=BLOCKS - copy only BLOCKS input blocks
- ibs=BYTES - read BYTES bytes at a time (default: 512)
- if=FILE - read from FILE instead of stdin
- iflag=FLAGS - read as per the comma separated symbol list
- obs=BYTES - write BYTES bytes at a time (default: 512)
- of=FILE - write to FILE instead of stdout
- oflag=FLAGS - write as per the comma separated symbol list
- seek=BLOCKS - skip BLOCKS obs-sized blocks at start of output
- skip=BLOCKS - skip BLOCKS ibs-sized blocks at start of input
- status=noxfer - suppress transfer statistics
Detalji
BLOCKS and BYTES may be followed by the following multiplicative suffixes: c =1, w =2, b =512, kB =1000, K =1024, MB =1000*1000, M =1024*1024, xM =M GB=1000*1000*1000, G =1024*1024*1024, and so on for T, P, E, Z, Y.
Each CONV symbol may be:
- ascii - from EBCDIC to ASCII
- ebcdic - from ASCII to EBCDIC
- ibm - from ASCII to alternate EBCDIC
- block - pad newline-terminated records with spaces to cbs-size
- unblock - replace trailing spaces in cbs-size records with newline
- lcase - change upper case to lower case
- nocreat - do not create the output file
- excl - fail if the output file already exists
- notrunc - do not truncate the output file
- ucase - change lower case to upper case
- swab - swap every pair of input bytes
- noerror - continue after read errors
- sync - pad every input block with NULs to ibs-size; when used with block or unblock, pad with spaces rather than NULs
- fdatasync - physically write output file data before finishing
- fsync - likewise, but also write metadata
Each FLAG symbol may be:
- append append mode (makes sense only for output; conv=notrunc suggested)
- direct use direct I/O for data
- directory - fail unless a directory
- dsync - use synchronized I/O for data
- sync - likewise, but also for metadata
- fullblock - accumulate full blocks of input (iflag only)
- nonblock - use non-blocking I/O
- noatime - do not update access time
- noctty - do not assign controlling terminal from file
- nofollow - do not follow symlinks
Sending a USR1 signal to a running ‘dd’ process makes it print I/O statistics to standard error and then resume copying.
- $ dd if=/dev/zero of=/dev/null& pid=$!
- $ kill -USR1 $pid; sleep 1; kill $pid
- 18335302+0 records in 18335302+0 records out 9387674624 bytes (9.4 GB) copied, 34.6279 seconds, 271 MB/s
Options are:
- --help display this help and exit
- --version - output version information and exit
Autori: Paul Rubin, David MacKenzie i Stuart Kemp.
Prijava bugova:
- Report dd bugs to bug-coreutils@gnu.org
- GNU coreutils home page: <http://www.gnu.org/software/coreutils/>
- General help using GNU software: <http://www.gnu.org/gethelp/>