-.SH "ASSEMBLER (PDP-11)"
-(indir = 0.)
-.br
-.B sys indir; call
-.PP
-The system call at the location
-.I call
-is executed.
-Execution resumes after the
-.I indir
-call.
-.PP
-On the PDP-11, the main purpose of
-.I indir
-is to allow a program to
-store arguments in system calls and execute them
-out of line in the data segment.
-This preserves the purity of the text segment.
-.PP
-If
-.I indir
-is executed indirectly,
-it is a no-op.
-If the instruction at the indirect
-location is not a system call,
-.I indir
-returns error code EINVAL;
-see
-.IR intro (2).