A PE file header indicates the windows operating system of what files need running a distinct file. It distinguishes between various forms of headers present in computer memory.

PE File Header
PE File Header | Image by 200 Degrees from Pixabay

For every executable file in the computer, there is a common object file format (COFF). It tells the user about the internal structure of the executable file. Knowledge about this assists a person to comprehend about functioning and design of the data. It helps in analyzing and segregating the folders better. There are several types of COFF. One such executable file format of COFF is PE. It stands for Portable Executable format.

PE file header:

The PE header occupies the first 64 bits of the file. It uses MZ, called as the magic number that defines the identifiable file type. PE Header helps in determining the compatible format to be used. It is an image file header that tells about the file location. The authentic structure of the PE header consists of 11 subsections. It consists of .exe construction, and the predominant parts consist of an image signature, file header, and optional header. Each of these sections has its functions and importance.

The structure:

The file header consists of MS-DOS stub, signature, COFF header, and an optional header. A sectional header succeeds in a PE file header, which helps to differentiate between different header types.

  • MS-DOS stub: The MS-DOS is a windows application that finds its use for the images. It finds its place before the .exe extension. It has a stub that tells the user if the image can be used and accessed. If the image is not accessible, it displays a message that the file is inaccessible in the DOS mode.
  • Signature: Signature of the file follow the stub. It identifies the data as an image file. It consists of 4 bytes in size. In it, the characters P and E precedes two zeros or null bytes.
  • COFF header: It is a header, i.e., present at the start of the file or the one that immediately proceeds the signature. It has a maximum limit of 96 sections and is a representative of both objects and images. It consists of different fields, including machines, number of parts, time date stamp, etc. All of these fields have different offsets and sizes.
  • Optional header: It is an optional header used in the file for image files only. It comprises standard fields that make use of the first 8 bytes. They consist of general information that determines the loading and execution of the image.

PE File Section:

The section names of the PE file header are an editable section of the file. It has to be studied well before making an edit. The edit of the header by using the ASCII characteristics is easy and uncomplicated. To every edit, there is a rule and protocol. Harming these can lead to damage to the files. With different sectors owning their importance, the PE header is an attractive field to explore. It helps a person to explore more of the world of files, its working, and execution.