.TH AS 1
.UC
.SH NAME
as \- assembler
.SH SYNOPSIS
.B as
[
.B \-u
] [
.B \-V
] [
.B \-o
objfile
] file ... 
.SH DESCRIPTION
.I As
assembles the concatenation of the named files.
The options are:
.TP
.B \-u
Treat all undefined symbols in the assembly as external globals.
.TP
.B \-\^V
Produce an object suitable for loading into an automatic text overlaid
program.
.TP
.B \-\^o
Use
.I objfil
for the name of the resultant object.  If this is omitted,
.I a.out
is used.  If no errors occurred during the assembly and if
there were no unresolved external references, it is made executable.
.P
The special file name
.B \-\-
serves two purposes.  It signals the end of all options and causes
.I stdin
to be read for input.  Thus it is now possible to pipe data to the
assembler:
.br
.sp
/lib/cpp -E foo.s | sed -e ';^#;/;' | as -o foo.o --
.br
.sp
The file name
.B \-\-
may be placed between normal files, when EOF is detected on 
.I stdin
the next file in the argument list is opened and read.
.br
.sp
If no input files are specified then 
.I stdin
is read.
.SH FILES
/tmp/atm1	temporary
.br
a.out	object
.SH "SEE ALSO"
adb(1), ld(1), nm(1), a.out(5)
.br
.I "UNIX Assembler Manual"
by D. M. Ritchie
.SH DIAGNOSTICS
When
an input file cannot be read, its name
followed by a question mark is typed and assembly
ceases.
When syntactic or semantic errors occur, a single-character diagnostic is typed out
together with the line number and the file name in which it
occurred.
Errors in pass 1 cause cancellation of pass 2.
The possible errors are:
.PP
.ta 3
)	Parentheses error
.br
]	Parentheses error
.br
<	String not terminated properly
.br
*	Indirection used illegally
.br
.li
\fB.\fP	Illegal assignment to `\fB.\fP'
.br
a	Error in address
.br
b	Branch instruction is odd or too remote
.br
e	Error in expression
.br
f	Error in local (`f' or `b') type symbol
.br
g	Garbage (unknown) character
.br
i	End of file inside an if
.br
m	Multiply defined symbol as label
.br
o	Word quantity assembled at odd address
.br
p	`\fB.\fP' different in pass 1 and 2
.br
r	Relocation error
.br
u	Undefined symbol
.br
x	Syntax error
.br
.SH BUGS
Syntax errors can cause incorrect line numbers
in following diagnostics.