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Full Discussion: Need specific byte positions of a file
Top Forums Shell Programming and Scripting Need specific byte positions of a file Post 302361395 by aigles on Tuesday 13th of October 2009 06:03:30 AM
Old 10-13-2009
Another way using dd :
Code:
dd if=filename bs=1 skip=642362 count=8

An example with the following input file (which contains a single record)
Code:
[001][002][003][004][005][006][007][008][009][010][011][012][013][014][015][016]
[017][018][019][020][021][022][023][024][025][026][027][028][029][030][031][032]
[033][034][035][036][037][038][039][040][041][042][043][044][045][046][047][048]
[049][050][051][052][053][054][055][056][057][058][059][060][061][062][063][064]
[065][066][067][068][069][070][071][072][073][074][075][076][077][078][079][080]
[081][082][083][084][085][086][087][088][089][090][091][092][093][094][095][096]
[097][098][099][100][101][102][103][104][105][106][107][108][109][110][111][112]
[113][114][115][116][117][118][119][120][121][122][123][124][125][126][127][128]
[129][130][131][132][133][134][135][136][137][138][139][140][141][142][143][144]
[145][146][147][148][149][150][151][152][153][154][155][156][157][158][159][160]
[161][162][163][164][165][166][167][168][169][170][171][172][173][174][175][176]
[177][178][179][180][181][182][183][184][185][186][187][188][189][190][191][192]
[193][194][195][196][197][198][199]

To extract bytes from 501 to 510 :
Code:
> dd if=inputfile bs=1 skip=500 count=10 2>/dev/null
[101][102]>

As you can see there is no line terminator in the output.

Jean-Pierre.
 

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