From 84210293d9f57b61abbee8639f102ff112ecfc7b Mon Sep 17 00:00:00 2001
From: Francois Fleuret <francois@fleuret.org>
Date: Wed, 4 Jul 2018 20:30:58 +0200
Subject: [PATCH] Added the -h option to force the remote host

---
 xremote.sh | 41 +++++++++++++++++++++++++++++++++++------
 1 file changed, 35 insertions(+), 6 deletions(-)

diff --git a/xremote.sh b/xremote.sh
index c093b62..7556470 100755
--- a/xremote.sh
+++ b/xremote.sh
@@ -35,12 +35,12 @@ function check_remote_is_defined () {
 
 function help () {
     cat <<EOF
-xremote.sh <script> [arguments]
+xremote.sh [-h remote_host] <script> [script arguments]
 
   This script takes a script as argument and executes it remotely in a
   temporary directory on a ssh-accessible server.
 
-  It parses the script first to find embedded arguments which defines
+  It parses the script first to find embedded arguments which define
   the hostname on which to run, the files to send, the files to get
   back when the execution is over, and commands to execute before
   running the executable remotely.
@@ -56,8 +56,11 @@ xremote.sh <script> [arguments]
     @XREMOTE_GET: *.dat
     @XREMOTE_PRE: ln -s /home/fleuret/data/pytorch ./data
 
-  If no argument is provided to @XREMOTE_HOST, the environment
-  variable \$XREMOTE_HOST is used instead
+  If the -h option is provided @XREMOTE_HOST is ignored.
+
+  If no argument is provided to @XREMOTE_HOST, and the -h option is
+  not specified, the environment variable \$XREMOTE_HOST is used
+  instead
 
   Contact <francois@fleuret.org> for comments.
 
@@ -75,7 +78,26 @@ function cleanup_remote_tmp () {
 
 ######################################################################
 
-[[ -x "$1" ]] || (help && exit 1)
+while [[ "$1" =~ ^- ]]
+do
+    case "$1"
+    in
+        -h)
+            shift
+            ARG_HOST="$1"
+            echo "xremote: remote forced to ${ARG_HOST}"
+            ;;
+        *)
+            echo "Unknown option $1"
+            exit 1
+            ;;
+    esac
+    shift
+done
+
+######################################################################
+
+[[ -a "$1" ]] || (help && exit 1)
 
 main="$(basename "$1")"
 
@@ -118,7 +140,8 @@ do
 
             HOST)
                 [[ "${REMOTE_DIR}" ]] && (exit "Remote host already defined!" >&2 && exit 1)
-                REMOTE_HOST="${value}"
+                REMOTE_HOST="${ARG_HOST}" # Host given in argument has priority
+                [[ "${REMOTE_HOST}" ]] || REMOTE_HOST="${value}"
                 [[ "${REMOTE_HOST}" ]] || REMOTE_HOST="${XREMOTE_HOST}"
                 [[ "${REMOTE_HOST}" ]] || (echo "xremote: No remote host specified." >&2 && exit 1)
                 REMOTE_DIR="$(ssh </dev/null "${REMOTE_HOST}" mktemp -d /tmp/xremote.from_"$(hostname)_$(date +%Y%m%d-%H%M%S)".XXXXXX)"
@@ -169,6 +192,12 @@ do
         label=$(echo "${line}" | sed -e 's/^.*@XREMOTE_\([^:]*\):.*$/\1/')
         value=$(echo "${line}" | sed -e 's/^.*@XREMOTE_[^:]*: *\(.*\)$/\1/')
         case "${label}" in
+            POST)
+                check_remote_is_defined
+                echo "xremote: ${value}"
+                ssh < /dev/null "${REMOTE_HOST}" "cd \"${REMOTE_DIR}\" && ${value}"
+                ;;
+
             GET)
                 check_remote_is_defined
                 ssh </dev/null "${REMOTE_HOST}" "cd \"${REMOTE_DIR}\" && tar 2>/dev/null c ${value}" | tar mxv
-- 
2.20.1