It only takes a minute to sign up. Connect and share knowledge within a single location that is structured and easy to search. From what I understand, a compiler makes a binary file that consists of 1's and 0's that a CPU can read. I have a binary file but how do I open it to see the 1's and 0's that are there?
A text editor says it can't open it According to this answer by tyranid :. Most Linux distros have hexdump by default but obviously not all. According to this answer by Emilio Bool :. All files on computers are stored as 1's and 0's.
Images, text files, music, executable applications, object files, etc. They are all 0's and 1's. The only difference is that they are interpreted differently depending upon what opens them. When you view a text file using cat , the executable cat in this case reads all the 1's and 0's and it presents them to you by converting them into characters from your relevant alphabet or language. When you view a file using an image viewer, it takes all the 1's and 0's and turns them into an image, depending on the format of the file and some logic to work it all out.
If you want to understand what an executable binary file does, you need to view it in a way which shows you the assembler language as a start , which you can do using,. NB: as Wildcard points out, it's important to note the files don't contain the characters 1 and 0 as you see them on the screen , they contain actual numeric data, individual bits of information which are either on 1 or off 0.
Even that description is only an approximation of the truth. They key point is that if you do find a viewer which shows you the 1's and 0's, even that is still interpreting the data from the file and then showing you the ASCII characters for 0 and 1. The data is stored in a binary format see the Binary number link above. Pierre-Olivier's community wiki entry covers this in more detail.
First and more important than this story of 0's and 1's , you have to understand that anything that the computer manipulates is encoded with numbers. A character is coded with a number, using character set tables. A pixel is coded with one or more numbers There are a lot of graphical formats For example, in standard 3-colors format, a yellow pixel is encoded as : for Red, for Green, 0 for Blue.
A binary-executable file is written in Assembly; each assembly instruction is coded as numbers. Secondly : each number can have multiple representations or notations. But I can also make groups of 16 apples. So I'll get one Group-of, and 7 lone apples. But how to represent more than 9 Group-of, or more of 9 alone-apples?
Simply, we use letters from A 10 to F The number 31 as in 31 apples is written as 1F in hexadecimal. On the same line, we can do group-of-two-apples. And group of two group-of-two apples, i. Then 23 is : 1 group-of-2x2x2x2-apples, 0 group-of-2x2x2-apples, 1 group-of-2x2-apples, 1 group of 2 apples, and 1 lone apple Which will be noted in binary. Physically, mechanisms allowing two states switches are easy to do, as well on disk that in memory storage.
Then translated - depending upon the data type - into their appropriate form letter A, yellow pixel or executed MOV instruction. You can then use a calculator to get the corresponding binary form. I would start with od octal dump , and depending on the system, may find tools such as objdump useful. You could open it in a hex editor which shows it as a series of hexadecimal values.
The Linux strings command prints the strings of printable characters in files, e. It's available on most linux systems. An important part about which you still seem confused: Hexadecimal values are just a different representation of binary values. That is where debuggers come into the picture, and on Linux, gdb is the defacto debugger. It helps you load a program, set breakpoints at specific places, analyze memory and CPU register, and do much more. It complements the other tools mentioned above and allows you to do much more runtime analysis.
One thing to notice is, once you load a program using gdb , you will be presented with its own gdb prompt. All further commands will be run in this gdb command prompt until you exit. We will use the "hello" program that we compiled earlier and use gdb to see how it works.
Once you are comfortable with using these native Linux binary analysis tools and understanding the output they provide, you can then move onto more advanced and professional open source binary analysis tools like radare2. The humble strings command can be useful to visualize text error messages which give hints of the binary functionalities.
These simple commands and tools can help you sail through the task of analyzing binary files. Image credits :. Get the highlights in your inbox every week.
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His primary interests are Security, Linux, Malware. He loves working on the command-line and is mostly interested in low-level software and understanding how things work. Opinions expressed here are my own and not that of my employer More about me. Recommended reading 7 Linux commands to use just for fun. Transfer files between your phone and Linux with this open source tool.
How I build command-line apps in JavaScript. Why I use Linux to manage my yoga studio. It looks like you're right. However it's quite some time ago that I looked into this so I don't remember why I put the find there. Without the additional fork this it's also way faster!
I just ran this, and it found all 'non-binary' files instead. Maybe the files you think are 'non-binary' are empty? Those show up, too as they are not text, I guess — t. Show 5 more comments. Here is a summary: The "-T" and "-B" switches work as follows.
GuyA GuyA 21 1 1 bronze badge. Using file. As this is an assignment, you would probably hate me if I gave you the complete solution ;- So here is a little hint: The grep command will output a list of binary files per default, if you search for a regular expression like. Michael Jaros Michael Jaros 4, 1 1 gold badge 21 21 silver badges 38 38 bronze badges.
Syed Syed 1 1 gold badge 8 8 silver badges 15 15 bronze badges. See the comments to this answer above - not all binary files are executables; your answer is wrong. The manpages says: -executable Matches files which are executable and directories which are searchable in a file name resolution sense. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access 2 system call, and so can be fooled by NFS servers which do UID mapping or root-squashing , since many systems implement access 2 in the client's kernel and so cannot make use of the UID mapping information held on the server.
Because this test is based only on the result of the access 2 system call, there is no guarantee that a file for which this test succeeds can actually be executed.
But for example, this will give me an error on pictures, music files, or others, or what is exactly a binary file in this case? So, you want all the files that are not plain-text, right? The OP explicitly mentioned "binary", not "executable" files.
Although the answer is not correct, I still find it very useful due to the power of find in folders with very large number of files, giving you a good first filtering. Sign up or log in Sign up using Google.
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