Questions tagged [byte]
18 questions
26
votes
3 answers
Byte count of "ls -l " versus that of "wc -c "
Is there any possible situation when
ls -l file.txt
is showing not the same number of bytes as
wc -c file.txt
In one script I found comparison of those two values. What could be the reason of that? Is it even possible to have different byte…
Rokas.ma
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19
votes
3 answers
How do I trim bytes from the beginning and end of a file?
I have a file, that has trash (binary header and footer) at the beginning and end of the file. I would like to know how to nuke these bytes. For an example, let's assume 25 bytes from the beginning. And, 2 bytes from the end.
I know I can use…
Evan Carroll
- 28,578
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19
votes
4 answers
Is there a oneliner that converts a binary file from little endian to big endian?
and vice versa.
I am running a RedHat if relevant.
Fermat's Little Student
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- 12
11
votes
2 answers
How do I find the first non-zero byte on a block device, with an optional offset?
I'm trying to find the first non-zero byte (starting from an optional offset) on a block device using dd and print its offset, but I am stuck. I didn't mention dd in the title as I figured there might be a more appropriate tool than dd to do this,…
ExploringQuest
- 113
- 5
5
votes
3 answers
What is the difference between a byte and a character (at least *nixwise)?
I understand that any character is comprised of one or more byte/s.
If I am not mistaken, at least in *nix operating systems, a character will generally (or totally?) be comprised of only one byte.
What is the difference between a byte and a…
variableexpander
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5
votes
5 answers
How to count the number of bytes in a file, grouping the same bytes?
Example: I have the file "mybinaryfile", and the contents in hex are:
A0 01 00 FF 77 01 77 01 A0
I need to know how many A0 bytes there are in this file, how many 01, and so on. The result could be:
A0: 2
01: 3
00: 1
FF: 1
77: 2
Is there some way…
Lawrence
- 329
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3
votes
1 answer
What is "length" of a string in Bourne shell compatibles' `${#string}`?
Arising from this discussion:
When I have (zsh 5.8, bash 5.1.0)
var="ASCII"
echo "${var} has the length ${#var}, and is $(printf "%s" "$var"| wc -c) bytes long"
the answer is simple: these are 5 characters, occupying five bytes.
Now, var=Müller…
Marcus Müller
- 21,602
- 2
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3
votes
2 answers
How to bury an invisible mark into lines of text?
How can I bury an invisible mark into random lines of text? Such a mark has to be there, though it will be invisible to someone reading that text printed out on the console.
I want to identify those lines by means of an invisible mark in order to,…
n.r.
- 2,173
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- 30
1
vote
4 answers
How to count the number of bytes in a very large file, grouping the same bytes?
I am searching for a way to get a statistics on a very large (multiple times larger than the available RAM) the outputs what byte values in the files are present and how often:
A0 01 00 FF 77 01 77 01 A0
I need to know how many A0 bytes there are…
Robert
- 163
- 6
1
vote
2 answers
What options does wget --report-speed take?
When I do this command:
wget --report-speed=type
they only type it accepts is bits. It won't have numbers, kilobits / kilobytes or bytes.
The help page (wget --help) says:
--report-speed=TYPE Output bandwidth as TYPE. TYPE can be…
Tim
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0
votes
1 answer
Why is od calculating decimal values wrong?
This question is related to the answer from enzotib to the question: How could I use Bash to find 2 bytes in a binary file, increase their values, and replace?
This converts the two bytes into its hex value:
$ echo -n $'\x1b\x1f' | od -tx2
0000000…
erik
- 16,959
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0
votes
1 answer
Convert variable from little endian to big endian
Working in Bash
I have a hex variable that I must convert from little endian to big endian
I am new to the entire concept of this and only learned about this about 20 minutes ago, so please bare with me.
My script determines a hex variable that…
Nir
- 1
- 2
0
votes
1 answer
print byte from number in awk
I can print a byte from a string literal like:
awk 'BEGIN {print "\001"}' | cat -v
But I need to print a byte of the result of a bitwise OR.
So how can I print a byte from a number?
Gawk is ok.
sedwho
- 5
- 2
0
votes
2 answers
Count bytes of filename
How can I know how many bytes does it weight the name of a filename? Just the file, not the full path.
I've tried this:
echo 'filename.extension' | wc -c
is this right?
Smeterlink
- 195
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0
votes
1 answer
Execute Program until specific amount of bytes has been returned on stdout, then terminate
Imagine I have the following program/script ./generate-infinite-byte-stream:
#!/bin/bash
echo -n 'hello'
sleep infinity
The infinite sleep command represents a network connection that may or may not deliver more data in the indefinite future that I…
masterxilo
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