1 files changed, 78 insertions, 0 deletions
diff --git a/appl/alphabet/main/cat.b b/appl/alphabet/main/cat.b
new file mode 100644
index 00000000..b19b1fd9
--- /dev/null
+++ b/appl/alphabet/main/cat.b
@@ -0,0 +1,78 @@
+implement Mainmodule;
+include "sys.m";
+	sys: Sys;
+include "draw.m";
+include "sh.m";
+include "alphabet/reports.m";
+	reports: Reports;
+		Report, report: import reports;
+include "alphabet.m";
+	alphabet: Alphabet;
+		Value: import alphabet;
+
+typesig(): string
+{
+	return "ff*";
+}
+
+init()
+{
+	sys = load Sys Sys->PATH;
+	alphabet = load Alphabet Alphabet->PATH;
+	reports = load Reports Reports->PATH;
+}
+
+quit()
+{
+}
+
+run(nil: ref Draw->Context, r: ref Reports->Report, nil: chan of string,
+		nil: list of (int, list of ref Alphabet->Value),
+		args: list of ref Alphabet->Value): ref Alphabet->Value
+{
+	fds: list of chan of ref Sys->FD;
+	for(; args != nil; args = tl args)
+		fds = (hd args).f().i :: fds;
+	f := chan of ref Sys->FD;
+	spawn catproc(f, rev(fds), r.start("print"));
+	return ref Value.Vf(f);
+}
+
+catproc(f: chan of ref Sys->FD, fds: list of chan of ref Sys->FD, reportc: chan of string)
+{
+	f <-= nil;
+	if((fd1 := <-f) == nil){
+		for(; fds != nil; fds = tl fds){
+			<-hd fds;
+			hd fds <-= nil;
+		}
+		reports->quit(reportc);
+	}
+	buf := array[8192] of byte;
+	for(; fds != nil; fds = tl fds){
+		fd0 := <-hd fds;
+		if(fd0 == nil){
+			p := array[2] of ref Sys->FD;
+			sys->pipe(p);
+			fd0 = p[0];
+			hd fds <-= p[1];
+		}else
+			hd fds <-= nil;
+		while((n := sys->read(fd0, buf, len buf)) > 0){
+			sys->write(fd1, buf, n);
+		}exception{
+		"write on closed pipe" =>
+			;
+		}
+	}
+	sys->write(fd1, array[0] of byte, 0);
+	reports->quit(reportc);
+}
+
+rev[T](l: list of T): list of T
+{
+	r: list of T;
+	for(; l != nil; l = tl l)
+		r = hd l :: r;
+	return r;
+}
+\ No newline at end of file