Procedure AssignPipe (Pipe_in, Pipe_out : Text) ;
AssignePipe creates a pipe, i.e. two file objects, one for input, one for output. What is written to Pipe_out, can be read from Pipe_in. Reading and writing happens through the usual Readln(Pipe_in,...) and Writeln (Pipe_out,...) procedures.
LinuxError is used to report errors:
Program Example36;
{ Program to demonstrate the AssignPipe function. }
Uses linux;
Var pipi,pipo : Text;
s : String;
begin
Writeln ('Assigning Pipes.');
assignpipe(pipi,pipo);
if linuxerror<>0 then
Writeln('Error assigning pipes !');
Writeln ('Writing to pipe, and flushing.');
Writeln (pipo,'This is a textstring');close(pipo);
Writeln ('Reading from pipe.');
While not eof(pipi) do
begin
Readln (pipi,s);
Writeln ('Read from pipe : ',s);
end;
close (pipi);
writeln ('Closed pipes.');
writeln
end.