Search results
Results from the WOW.Com Content Network
However, file archivers like WinRAR can still treat a self-extracting file as if it were any other type of compressed file. By using a file archiver, users can view or decompress self-extracting files they received without running executable code (for example, if they are concerned about viruses). [citation needed]
WinRAR is a trialware file archiver utility, developed by Eugene Roshal of win.rar GmbH. It can create and view archives in RAR or ZIP file formats, [ 6 ] and unpack numerous archive file formats. To enable the user to test the integrity of archives, WinRAR embeds CRC32 or BLAKE2 checksums for each file in each archive.
RAR files can only be created with proprietary WinRAR (Windows), RAR [9] for Android, command-line RAR (available for Windows, macOS, Linux, and FreeBSD), and other software that has written permission from Alexander Roshal or uses copyrighted code under license from Roshal. The software license agreements forbid reverse engineering.
ZPAQ will use an E8E9 transform (see: BCJ) to improve the compression of x86 code typically found in .exe and .dll files. An E8E9 transform scans for CALL and JMP instructions (opcodes E8 and E9 hex) and replaces their relative addresses with absolute addresses. Then it inserts code into the PCOMP section to perform the inverse transform.
In computer programming, unreachable code is part of the source code of a program which can never be executed because there exists no control flow path to the code from the rest of the program. [ 1 ] Unreachable code is sometimes also called dead code , [ 2 ] [ 3 ] although dead code may also refer to code that is executed but has no effect on ...
The environment of an EXE program run by DOS is found in its Program Segment Prefix.. EXE files normally have separate segments for the code, data, and stack. Program execution begins at address 0 of the code segment, and the stack pointer register is set to whatever value is contained in the header information (thus if the header specifies a 512 byte stack, the stack pointer is set to 200h).
Self-modifying code is sometimes used to overcome limitations in a machine's instruction set. For example, in the Intel 8080 instruction set, one cannot input a byte from an input port that is specified in a register. The input port is statically encoded in the instruction itself, as the second byte of a two byte instruction.
BIOS interrupt calls perform hardware control or I/O functions requested by a program, return system information to the program, or do both. A key element of the purpose of BIOS calls is abstraction - the BIOS calls perform generally defined functions, and the specific details of how those functions are executed on the particular hardware of the system are encapsulated in the BIOS and hidden ...