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-rwxr-xr-xdpmert/line_mediator.pl116
1 files changed, 0 insertions, 116 deletions
diff --git a/dpmert/line_mediator.pl b/dpmert/line_mediator.pl
deleted file mode 100755
index bc2bb24c..00000000
--- a/dpmert/line_mediator.pl
+++ /dev/null
@@ -1,116 +0,0 @@
-#!/usr/bin/perl -w
-#hooks up two processes, 2nd of which has one line of output per line of input, expected by the first, which starts off the communication
-
-# if you don't know how to fork/exec in a C program, this could be helpful under limited cirmustances (would be ok to liaise with sentserver)
-
-#WARNING: because it waits for the result from command 2 after sending every line, and especially if command 1 does the same, using sentserver as command 2 won't actually buy you any real parallelism.
-
-use strict;
-use IPC::Open2;
-use POSIX qw(pipe dup2 STDIN_FILENO STDOUT_FILENO);
-
-my $quiet=!$ENV{DEBUG};
-$quiet=1 if $ENV{QUIET};
-sub info {
- local $,=' ';
- print STDERR @_ unless $quiet;
-}
-
-my $mode='CROSS';
-my $ser='DIRECT';
-$mode='PIPE' if $ENV{PIPE};
-$mode='SNAKE' if $ENV{SNAKE};
-$mode='CROSS' if $ENV{CROSS};
-$ser='SERIAL' if $ENV{SERIAL};
-$ser='DIRECT' if $ENV{DIRECT};
-$ser='SERIAL' if $mode eq 'SNAKE';
-info("mode: $mode\n");
-info("connection: $ser\n");
-
-
-my @c1;
-if (scalar @ARGV) {
- do {
- push @c1,shift
- } while scalar @ARGV && $c1[$#c1] ne '--';
-}
-pop @c1;
-my @c2=@ARGV;
-@ARGV=();
-(scalar @c1 && scalar @c2) || die qq{
-usage: $0 cmd1 args -- cmd2 args
-all options are environment variables.
-DEBUG=1 env var enables debugging output.
-CROSS=1 hooks up two processes, 2nd of which has one line of output per line of input, expected by the first, which starts off the communication. crosses stdin/stderr of cmd1 and cmd2 line by line (both must flush on newline and output. cmd1 initiates the conversation (sends the first line). default: attempts to cross stdin/stdout of c1 and c2 directly (via two unidirectional posix pipes created before fork).
-SERIAL=1: (no parallelism possible) but lines exchanged are logged if DEBUG.
-if SNAKE then stdin -> c1 -> c2 -> c1 -> stdout.
-if PIPE then stdin -> c1 -> c2 -> stdout (same as shell c1|c2, but with SERIAL you can see the intermediate in real time; you could do similar with c1 | tee /dev/fd/2 |c2.
-DIRECT=1 (default) will override SERIAL=1.
-CROSS=1 (default) will override SNAKE or PIPE.
-};
-
-info("1 cmd:",@c1,"\n");
-info("2 cmd:",@c2,"\n");
-
-sub lineto {
- select $_[0];
- $|=1;
- shift;
- print @_;
-}
-
-if ($ser eq 'SERIAL') {
- my ($R1,$W1,$R2,$W2);
- my $c1p=open2($R1,$W1,@c1); # Open2 R W backward from Open3.
- my $c2p=open2($R2,$W2,@c2);
- if ($mode eq 'CROSS') {
- while(<$R1>) {
- info("1:",$_);
- lineto($W2,$_);
- last unless defined ($_=<$R2>);
- info("1|2:",$_);
- lineto($W1,$_);
- }
- } else {
- my $snake=$mode eq 'SNAKE';
- while(<STDIN>) {
- info("IN:",$_);
- lineto($W1,$_);
- last unless defined ($_=<$R1>);
- info("IN|1:",$_);
- lineto($W2,$_);
- last unless defined ($_=<$R2>);
- info("IN|1|2:",$_);
- if ($snake) {
- lineto($W1,$_);
- last unless defined ($_=<$R1>);
- info("IN|1|2|1:",$_);
- }
- lineto(*STDOUT,$_);
- }
- }
-} else {
- info("DIRECT mode\n");
- my @rw1=POSIX::pipe();
- my @rw2=POSIX::pipe();
- my $pid=undef;
- $SIG{CHLD} = sub { wait };
- while (not defined ($pid=fork())) {
- sleep 1;
- }
- my $pipe = $mode eq 'PIPE';
- unless ($pipe) {
- POSIX::close(STDOUT_FILENO);
- POSIX::close(STDIN_FILENO);
- }
- if ($pid) {
- POSIX::dup2($rw1[1],STDOUT_FILENO);
- POSIX::dup2($rw2[0],STDIN_FILENO) unless $pipe;
- exec @c1;
- } else {
- POSIX::dup2($rw2[1],STDOUT_FILENO) unless $pipe;
- POSIX::dup2($rw1[0],STDIN_FILENO);
- exec @c2;
- }
- while (wait()!=-1) {}
-}