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diff --git a/reproduce/src/bash/download-multi-try b/reproduce/src/bash/download-multi-try
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+#!.local/bin/bash
+#
+# Attempt downloading multiple times before crashing whole pipeline. From
+# the top paper directory (for the shebang above), this script must be run
+# like this:
+#
+#   $ ./download-multi-try downloader lockfile input-url downloaded-name
+#
+# Due to temporary network problems, a download may fail suddenly, but
+# succeed in a second try a few seconds later. Without this script that
+# temporary glitch in the network will permanently crash the pipeline and
+# it can't continue. The job of this script is to be patient and try the
+# download multiple times before crashing the whole pipeline.
+#
+# LOCK FILE: Since there is ultimately only one network port to the outside
+# world, downloading is done much faster in serial, not in parallel. But
+# the pipeline's processing may be done in parallel (with multiple threads
+# needing to download different files at the same time). Therefore, this
+# script uses the `flock' program to only do one download at a time. To
+# benefit from it, any call to this script must be given the same lock
+# file.
+#
+# Original author:
+#     Mohammad Akhlaghi <mohammad@akhlaghi.org>
+# Contributing author(s):
+# Copyright (C) 2019, Mohammad Akhlaghi.
+#
+# This script is free software: you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by the
+# Free Software Foundation, either version 3 of the License, or (at your
+# option) any later version.
+#
+# This script is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General
+# Public License for more details. See <http://www.gnu.org/licenses/>.
+
+
+
+
+
+# Script settings
+# ---------------
+# Stop the script if there are any errors.
+set -e
+
+
+
+
+
+# Input arguments and necessary sanity checks.
+inurl="$3"
+outname="$4"
+lockfile="$2"
+downloader="$1"
+if [ "x$downloader" = x ]; then
+    echo "$0: downloader (first argument) not given."; exit 1;
+fi
+if [ "x$lockfile" = x ]; then
+    echo "$0: lock file (second argument) not given."; exit 1;
+fi
+if [ "x$inurl" = x ]; then
+    echo "$0: full input URL (third argument) not given."; exit 1;
+fi
+if [ "x$outname" = x ]; then
+    echo "$0: output name (fourth argument) not given."; exit 1;
+fi
+
+
+
+
+
+# Try downloading multiple times before crashing
+counter=0
+maxcounter=10
+while [ ! -f "$outname" ]; do
+
+    # Increment the counter. We need the `counter=' part here because
+    # without it the evaluation of arithmetic expression will be like and
+    # error and the script is set to crash on errors.
+    counter=$((counter+1))
+
+    # If we have passed a maximum number of trials, just exit with
+    # a failed code.
+    if (( counter > maxcounter )); then
+        echo
+	echo "Failed $maxcounter download attempts: $outname"
+        echo
+	exit 1
+    fi
+
+    # If this isn't the first attempt print a notice and wait a little for
+    # the next trail.
+    if (( counter > 1 )); then
+	tstep=$((counter*5))
+        echo "Download trial $counter for '$outname' in $tstep seconds."
+        sleep $tstep
+    fi
+
+    # Attempt downloading the file (one-at-a-time).
+    flock "$lockfile" bash -c \
+          "if ! $downloader -O$outname $inurl; then rm -f $outname; fi"
+done
+
+
+
+
+
+# Return successfully
+exit 0