Login or Register to Ask a Question and Join Our Community

Linux and UNIX Man Pages

Linux & Unix Commands - Search Man Pages

yasm_objfmts(7) [debian man page]

YASM_OBJFMTS(7) 					   Yasm Supported Object Formats					   YASM_OBJFMTS(7)

NAME

       yasm_objfmts - Yasm Supported Object Formats

SYNOPSIS

       yasm -f objfmt ...

DESCRIPTION

       The standard Yasm distribution includes a number of modules for different object formats (Yasm's primary output).

       The object format is selected on the yasm(1) command line by use of the -f objfmt command line option.

BIN

       The "bin" object format produces a flat-format, non-relocatable binary file. It is appropriate for producing DOS .COM executables or things
       like boot blocks. It supports only 3 sections and those sections are written in a predefined order to the output file.

COFF

       The COFF object format is an older relocatable object format used on older Unix and compatible systems, and also (more recently) on the
       DJGPP development system for DOS.

DBG

       The "dbg" object format is not a "real" object format; the output file it creates simply describes the sequence of calls made to it by Yasm
       and the final object and symbol table information in a human-readable text format (that in a normal object format would get processed into
       that object format's particular binary representation). This object format is not intended for real use, but rather for debugging Yasm's
       internals.

ELF

       The ELF object format really comes in two flavors: "elf32" (for 32-bit targets) and "elf64" (for 64-bit targets). ELF is a standard object
       format in common use on modern Unix and compatible systems (e.g. Linux, FreeBSD). ELF has complex support for relocatable and shared
       objects.

MACHO

       The Mach-O object format really comes in two flavors: "macho32" (for 32-bit targets) and "macho64" (for 64-bit targets). Mach-O is used as
       the object format on MacOS X. As Yasm currently only supports x86 and AMD64 instruction sets, it can only generate Mach-O objects for
       Intel-based Macs.

RDF

       The RDOFF2 object format is a simple multi-section format originally designed for NASM. It supports segment references but not WRT
       references. It was designed primarily for simplicity and has minimalistic headers for ease of loading and linking. A complete toolchain
       (linker, librarian, and loader) is distributed with NASM.

WIN32
       The Win32 object format produces object files compatible with Microsoft compilers (such as Visual C++) that target the 32-bit x86 Windows
       platform. The object format itself is an extended version of COFF.

WIN64
       The Win64 object format produces object files compatible with Microsoft compilers that target the 64-bit "x64" Windows platform. This
       format is very similar to the win32 object format, but produces 64-bit objects.

XDF

       The XDF object format is essentially a simplified version of COFF. It's a multi-section relocatable format that supports 64-bit physical
       and virtual addresses.

SEE ALSO

       yasm(1), yasm_arch(7)

AUTHOR

       Peter Johnson <peter@tortall.net>
	  Author.

COPYRIGHT

       Copyright (C) 2006 Peter Johnson

Yasm								   February 2007						   YASM_OBJFMTS(7)

Check Out this Related Man Page

MACH-O(5)							File Formats Manual							 MACH-O(5)

NAME

       Mach-O - Mach-O assembler and link editor output

SYNOPSIS

       #include <mach-o/loader.h>
       #include <mach-o/nlist.h>
       #include <mach-o/stab.h>
       #include <mach-o/reloc.h>

DESCRIPTION

       The  object  files  produced  by the assembler and link editor are in Mach-O (Mach object) file format.	The file name a.out is the default
       output file name of the assembler as(1) and the link editor ld(1) The format of the object file however is not 4.3BSD a.out format  as  the
       name  suggests,	but  rather  Mach-O  format.  The link editor will make a.out executable if the resulting format is an executable type and
       there were no errors and no unresolved external references.

       The complete description of a Mach-O file is given in a number of include files.  The file <mach-o/loader.h> describes the headers,  <mach-
       o/nlist.h> describes the symbol table entries with <mach-o/stab.h> supplementing it, and <mach-o/reloc.h> describes the relocation entries.

       The  actual  instructions and data used by the program represented by a Mach-O file are the contents of its sections.  Sections are grouped
       together in segments.  Each section carries with it, in its header, the information as to which segment it belongs in.  When  a	file  type
       that  is  executable  is  created  the sections are placed in their proper segment and all the segment headers are created and the segments
       themselves are padded out to the segment alignment (typically the target pagesize).  For the object file type produced by an assembler  (or
       by the link editor for further linking) all the sections are placed in one segment for compactness.

       When  the  kernel executes a Mach-O file it maps in the object file's segments, the dynamic link editor (if used) and creates the thread(s)
       for execution.  Any part of the object file that is not part of a segment is not mapped in for execution.  For executable using the dynamic
       link  editor  the  headers  and other link edit information is needed to execute the file.  These parts include the relocation entries, the
       symbol table and the string table.  These parts are mapped in with the use of the link editor's -seglinkedit option which creates a segment
       that contains these parts.  These parts can be stripped down with the -S option to ld(1) or various options to strip(1).

SEE ALSO

       as(1), ld(1), nm(1), gdb(1), stab(5), strip(1)

Apple Computer, Inc.						 October 22, 2001							 MACH-O(5)
Man Page