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From Leo's Notes
This page was last edited on 10 April 2017, at 17:02.
Created page with " == Manipulating by Bytes == Use the {{code|iflag=skip_bytes,count_bytes}} flags when working with data in bytes. The {{code|bs}} block size value will be ignored when these f..." |
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== Manipulating by Bytes == | == Manipulating by Bytes == | ||
Use the {{code|iflag=skip_bytes,count_bytes}} flags when working with data in bytes. The {{code|bs}} block size value will be ignored when these flags are used. | Use the {{code|1=iflag=skip_bytes,count_bytes}} flags when working with data in bytes. The {{code|bs}} block size value will be ignored when these flags are used. | ||
Question: When using the {{code|count_bytes}} flag, is this equivalent to {{code|bs=1}}? | Question: When using the {{code|count_bytes}} flag, is this equivalent to {{code|1=bs=1}}? | ||
=== Offset / Skipping Bytes === | === Offset / Skipping Bytes === | ||
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{{highlight|lang=terminal|code= | {{highlight|lang=terminal|code= | ||
$ dd if=blah.dat iflag=skip_bytes,count_bytes skip=199232000 | $ dd if=blah.dat iflag=skip_bytes,count_bytes skip=199232000 {{!}} xxd | ||
}} | }} | ||
To get only 200 bytes of data instead: | To get only 200 bytes of data instead: | ||
{{highlight|lang=terminal|code= | {{highlight|lang=terminal|code= | ||
$ dd if=blah.dat iflag=skip_bytes,count_bytes skip=199232000 count=200 | $ dd if=blah.dat iflag=skip_bytes,count_bytes skip=199232000 count=200 {{!}} xxd | ||
}} | }} | ||
Or 2 kilobytes (2048 bytes): | Or 2 kilobytes (2048 bytes): | ||
{{highlight|lang=terminal|code= | {{highlight|lang=terminal|code= | ||
$ dd if=blah.dat iflag=skip_bytes,count_bytes skip=199232000 count=2k | $ dd if=blah.dat iflag=skip_bytes,count_bytes skip=199232000 count=2k {{!}} xxd | ||
}} | }} | ||
[[Category:Linux]] | [[Category:Linux]] | ||
Revision as of 17:02, 10 April 2017
Manipulating by Bytes
Use the iflag=skip_bytes,count_bytes flags when working with data in bytes. The bs block size value will be ignored when these flags are used.
Question: When using the count_bytes flag, is this equivalent to bs=1?
Offset / Skipping Bytes
If you need to extract a chunk of data, say everything past byte 199232000 from a file:
$ dd if=blah.dat iflag=skip_bytes,count_bytes skip=199232000 | xxd
To get only 200 bytes of data instead:
$ dd if=blah.dat iflag=skip_bytes,count_bytes skip=199232000 count=200 | xxd
Or 2 kilobytes (2048 bytes):
$ dd if=blah.dat iflag=skip_bytes,count_bytes skip=199232000 count=2k | xxd