as -- assembler


   as [-VTm] [-Q yn] [-Y key,dir] [-o objfile] [-t cpu] file . . .


The as command produces an object file from the concatenation of the specified assembly language input files. At least one source file must be specified, except when the -V option is given. The name ``-''' designates the standard input, and may be specified anywhere within the list of files.

The recognized assembly language does not include a general macro processing capability. Instead, as provides for optional preprocessing of the input by the m4 command. [See m4(1).]

The following options may be specified in any order:

Writes the assembler's packaging, release, and version information on the standard error output. As a special case, the assembler does no other processing if no input files are specified.

Accepts input that contains old-style (COFF) directives. Nevertheless, most such directives are still ineffective, as the assembler generates an ELF object file.

Sends the input through the m4 macro processing command prior to assembly. All file operands are passed unmodified to the m4 command. (By using the ``--'' option-terminator, m4 options can be preserved and passed through to the m4 command; see the EXAMPLES section, below.) If present, the predefined macros file, LIBDIR/cm4defs, will be given to the m4 command as the initial input file.

-Q yn
Appends the assembler's release information to the ``.comment'' section of the generated output object file if yn is ``y''; otherwise (if yn is ``n'' or if no -Q option is specified), nothing is added.

-Y key,dir
Uses the directory dir to find the files specified by key: the m4 macro processing command (m), the predefined macros file (d), or both.

-o objfile
Causes objfile to be the name of the generated output object file. If no -o is specified, then the output object file is created in the current directory with a name that depends on the specified input files. If an input file with a name that ends with ``.s'' is present, the output file name is formed by replacing the suffix of the first such name with ``.o''; otherwise, the output file is ``a.out''.

-t cpu
Specifies the target processor to be cpu, which may be ``486'' (the default), ``386'', or ``pentium''. This option causes code generation specifically tuned to the selected processor.


Send, in order, ./cm4defs (if it exists) and mydefs and sys/file.s through m4 with the macro K predefined to be ``7'', assemble the output of m4, and generate the ELF object file output in ./file.o:
   as -m -Yd,. -- -DK=7 mydefs sys/file.s




language-specific message file [See LANG on environ(5).]


a.out(4), cc(1), Intro(3elf), ld(1), m4(1), nm(1), strip(1)


The m4 macro processor is not line-oriented and recognizes many regular identifiers as its keywords (index and len, for example). Thus, preprocessing compiler-generated assembly language with m4 requires care.

Whenever possible, you should access the assembler through a compilation system interface program such as cc.

This command has been updated to handle Intel Pentium III Streaming SIMD instructions; see ``Pentium III extended floating point support'' in New features for more information.

© 2004 The SCO Group, Inc. All rights reserved.
UnixWare 7 Release 7.1.4 - 25 April 2004