Questions tagged [od]
The od tag has no usage guidance.
37
questions
2
votes
0
answers
72
views
Should programs terminate on ENOSPC error?
In bash, the command hexdump -C /dev/urandom > hexdump.txt does not terminate.
It keeps going indefinitely, even if the filesystem is full.
read(0, "\326\210L0\rL<\177\207\214\3\2237\vi\315\...
- 31
2
votes
2
answers
2k
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How to format hexdump as xxd, possible for xxd -revert?
I wish to dump the raw content of a SD card into a file for inspection. Most parts of it are zeroes. Learnt from this SuperUser answer I could use pv to show the progress of od and hexdump. Both ETA ...
- 335
1
vote
1
answer
68
views
With what letters does OD utility separate each byte things, according to POSIX?
On my Termux, for example, the following can be obtained:
$ od -A n -t x1 /dev/urandom | head -n 2
e3 5d bf 57 fb 8b 63 06 4a 18 fe 28 73 8f 3e c0
9f 08 6b d4 2d 38 2c 68 3c 51 83 1e 71 7b 57 2b
As ...
user451199
8
votes
2
answers
10k
views
What is the difference between the od, hd, hexdump and xxd commands?
What is the difference between the od, hd, hexdump and xxd commands ?
They are all commands for dumping files and they can all dump it in various formats such as hexadecimal, octal or binary. Why ...
- 285
0
votes
1
answer
4k
views
Convert received data bytes in serial to hex text
Hi now I write bytes data (for eg, \x00\x11\x22) from my PC to serial port of my device running unix at the ttyS1 port. I am able to print the data using either
cat /dev/ttyS1
od -x < /dev/ttyS1
...
- 157
2
votes
2
answers
2k
views
Undump od (octal or hex dump) in Version 6 Unix
od (octal dump) command is implemented in Unix since Version 1. However, I couldn't find a reverse command in the Version 6 Unix manual (1975). Modern ways of reversing od with either xxd or sed do ...
- 548
1
vote
1
answer
480
views
od command to print all the values
I am running the od command as od -b myfile to convert a file I have into image pixels. I need to see all the values but because they are too many the command prints the following:
0000000 000 000 ...
- 13
1
vote
1
answer
2k
views
Removing control M characters from a given file and to remove newline character if it is the only character in the entire file
We have a file named as abc.txt and its a empty file. Due to some junk or control M characters, the file size is populated as 5 byte file. In order to have clean file we are using dos2unix command to ...
- 508
0
votes
2
answers
443
views
Is it correct that `od` can't show binary number?
Is it correct that od can't show binary number? I can't find an argument to provided to its -t option for showing binary number.
I feel it is natural to expect od to show binary number, or do I miss ...
- 100k
0
votes
1
answer
2k
views
Convert text file to non-iso extended ascii file
I have a file which is Non-ISO Extended ASCII type. I can't see its content just by opening it normally via cat or vim.
However, I'm able to see its content in readable form with this command...
od -...
- 1
2
votes
1
answer
179
views
Understanding the od utility output in regards to floats 'od -t f'
I am making my own od utility based on the Single UNIX Specification and I am confused on how the representation of floats is handled e.g. od -t f.
I have a perfectly functioning utility otherwise ...
- 159
5
votes
3
answers
4k
views
Explanation for the meaning of content of the /var/run/utmp file
I would like to understand the content of the following file system /var/run/utmp. When I use the command od to open it I see the following:
[john@iceman ~]$ od -c /var/run/utmp
0000000 002 \0 \0 ...
user308606
1
vote
1
answer
47
views
Insert OD output in another file
I have output from an od command (without access to the original file). Is it possible for me to get the binary data and insert it into another file with a programming language, like python?
Here is ...
- 11
-2
votes
1
answer
723
views
How does od treat symbols after `\x7f`?
The following command passes to od symbols from \x00 to \xff:
$ seq 0 255 | awk '{printf("%c", $0)}' | od -c
But what I get is:
0000000 \0 001 002 003 004 005 006 \a \b \t \n \v \f \r 016 ...
- 3,273
3
votes
2
answers
1k
views
What are those numbers on the left of od output?
I checked the od man page, but it does not explain this. What do the numbers on the left column of the od output mean?
- 135
1
vote
1
answer
623
views
How to prevent octal dump (od) returning?
I am trying to read some output from /dev/ttyUSB0, using od on Ubuntu. So I used this command:
od -x --endian=big < /dev/ttyUSB0
When I used it yesterday it was not blocking and just showed stuff ...
- 11
0
votes
3
answers
277
views
How to improve performance in generating MAC addresses with od?
In my script I need to randomly generate MAC addresses. The code below is from a larger script extracted, that's why the MAC address calculation is in a separate function.
This works fine with the ...
- 145
4
votes
3
answers
3k
views
Portable one-byte per line hex dump
Suppose we want a minimalist one-byte per line ASCII hex dump. Under Linux using GNU od, this works:
echo foo | od -An -tx1 -w1 -v
Output:
66
6f
6f
0a
But that won't work with BSD derivatives,...
- 7,073
1
vote
2
answers
542
views
What does the '005' mean in the output of linux command od?
I have a file called input_file, the following is the contents of input_file:
$ cat input_file
1
2
3
4
5
6
7
8
9
then I run the following command:
$ od -to2 input_file
...
- 263
7
votes
2
answers
11k
views
Octals 302 240 together seem to correspond to non-breaking space
By looking at a particular line of a text file (say, the 1123th, see below), it seems that there is a non-breaking space, but I am not sure:
$ cat myfile.csv | sed -n 1123p | cut -f2
Lisztes feher
$ ...
- 205
1
vote
1
answer
169
views
od prints extra value [closed]
I have a binary file containing 4-byte floats. I want to print these floats using od. However, od prints one additional value at the very first position. What is going on here?
The file looks like ...
0
votes
1
answer
2k
views
Commands for data manipulation of binary to octave/hex formats?
I need to convert binary data to hex/octave/any suitable format and back to binary when I am splitting one big 1GB file into files containing 777 events each which are not of the same size such that ...
- 6,848
15
votes
3
answers
113k
views
Convert binary mode to text mode and the reverse option
I converted a simple binary file into a text file with:
od –t x1 Check.tar | cut –c8- > Check.txt
Which gives a content similar to:
64 65 76 2f 6e 75 6c 6c 00 00 00 00 00 00 00 00
00 00 00 00 00 ...
- 7,031
13
votes
1
answer
6k
views
Removing line numbers from `od`'s output
Is there any flag to od to make it not output line numbers in the result?
- 1,805
3
votes
1
answer
1k
views
Can't use `od` command with directories
I'm trying to use the od command in a directory in OSX but it doesn't proceed and it results in the error message:
od: .: Is a directory
Could you please help me with it or any equivalent command?
- 31
5
votes
1
answer
997
views
Interpreting octal dump without options
$ echo "hello" | od
0000000 062550 066154 005157
0000006
I know that the first column represents the byte offset. But I don't see how the other numbers are formed. According to man the above should ...
- 330
2
votes
0
answers
1k
views
OpenWRT missing OD (octal dump)
I have a bash function using od command.
Now I'm trying to run in on OpenWRT and see that in has not od.
Also can't find it using install from opkg, because I can't find it.
Is there a possibility to ...
- 131
2
votes
1
answer
1k
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Understanding `od -c` output
I've got a text file that I'm trying to debug an encoding issue in. I ran the file through od -c and got the following output:
3457540 , " t e x t " : " 302 241 Q u 303 251
My ...
- 123
2
votes
1
answer
207
views
understanding od -a option
In Linux, the --type a option in od is explained as
--type=
Select the format in which to output the file data
…
a
named ...
- 4,980
0
votes
1
answer
289
views
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 ...
- 17.1k
4
votes
1
answer
340
views
od emulation for directories
I was wondering why od(1) used to work in UNIX but doesn't work in GNU/Linux. There is a nice answer on serverfault. The next question is, are you aware of any tools that can emulate od behavior to ...
- 2,873
6
votes
3
answers
14k
views
How to change the default line length for od and hexdump
Is there any way to change the default line length for the od and hexdump commands? Can't see anything apropriate in the man pages.
- 593
14
votes
2
answers
34k
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How to interpret an octal or hex dump of a binary file?
The binary file has strings and some numbers, If I do
od -c filename or strings filename, I can see the strings properly. But, what about numbers? They are in some weird format.
The text after doing ...
user14039
14
votes
2
answers
4k
views
Can hd and od replace each other?
hd and od are both dump viewers of binary content. Can hd be used wherever od is and vice versa?
- 100k
79
votes
2
answers
71k
views
Output from ls has newlines but displays on a single line. Why?
I think I may be overlooking a relatively fundamental point regarding shell. Output from the ls command by default separates output with newlines, but the shell displays the output on a single line.
...
- 1,009
12
votes
7
answers
30k
views
get numeric ASCII value for a character
I'm trying to write a shell script which asks for an ASCII character in the range A-Z or a-z and returns its equivalent numerical value. For example, the output might look like the following:
scarlet$...
- 207
4
votes
2
answers
2k
views
How is the octal 2-byte output calculated from od
I'm struggling to work out what the octal 2-byte output from the od command is. I understand the octal output (-b flag) but the octal 2-byte is a mystery to me (-o)
Can someone shed some light on how ...
- 1,009