diff -r dc5c210295d0 -r f466b4c7d9b1 streamlet-examples/__relpipe_in_filesystem_script_exiv2
--- a/streamlet-examples/__relpipe_in_filesystem_script_exiv2	Sat Jan 18 16:41:59 2020 +0100
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,80 +0,0 @@
-#!/bin/bash
-
-# Relational pipes
-# Copyright © 2020 František Kučera (Frantovo.cz, GlobalCode.info)
-#
-# This program 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, version 3 of the License.
-#
-# This program 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.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program. If not, see <http://www.gnu.org/licenses/>.
-
-
-# This streamlet provides EXIF metadata. It calls the tool exiv2.
-# With no options it returns "Image size", "Copyright" and "Exif comment" attributes.
-# Specific attributes can be selected using options – e.g. --option 'attribute' 'Image size'
-# List of available attributes can be obtained by directly calling the exiv2 command on a image file.
-# Two additional attributes are provided by this streamlet: "Image height" and "Image width" (they are extracted from "Image size").
-
-
-. "$(dirname $0)/streamlet-common.sh"
-
-processMessage_WAITING_FOR_OUTPUT_ATTRIBUTES_METADATA() {
-	streamletFields=()
-
-	for (( i=0; i<${#optionNames[@]}; i++)); do
-		if [[ "x${optionNames[$i]}" == "xattribute" ]]; then
-			streamletFields+=("${optionValues[$i]}");
-		elif [[ "x${optionNames[$i]}" == "xprefix" ]]; then
-			pdfPrefix="${optionValues[$i]}";
-		else
-			echo "Unsupported option: ${optionNames[$i]}" >&2
-		fi
-	done
-
-	if [[ -z "$streamletFields" ]]; then
-		streamletFields=( "Image size" "Copyright" "Exif comment" );
-	fi
-
-	for (( i=0; i<${#streamletFields[@]}; i++)); do
-		if [[ "x${streamletFields[$i]}" == "xImage height" ]] ||[[ "x${streamletFields[$i]}" == "xImage width" ]]; then local type="integer"; else local type="string"; fi
-		send OUTPUT_ATTRIBUTE_METADATA "${outputAttributeAliases[$i]-$pdfPrefix${streamletFields[$i]}}"    "$type"
-	done
-
-	send WAITING_FOR_INPUT_ATTRIBUTES
-}
-
-processMessage_WAITING_FOR_OUTPUT_ATTRIBUTES() {
-	local streamletInfo streamletValid value isNull;
-
-	[[ -d "$currentFile" ]] || streamletInfo="$(exiv2 "$currentFile")";
-	streamletValid="$?";
-
-	for (( i=0; i<${#streamletFields[@]}; i++)); do
-		value="$(echo "$streamletInfo" | grep -P "^\Q${streamletFields[$i]}\E\s*:" | sed -E 's/[^:]+:\s+(.*)/\1/g' | tr -d '\n';)"; # the field name must not contain "\E"
-
-		if   [[ -z "$value" ]] && [[ "x${streamletFields[$i]}" == "xImage width"  ]]; then value="$(echo "$streamletInfo" | grep -E 'Image size\s*:\s*[0-9]+ x [0-9]+' | sed -E 's/Image size\s*:\s*([0-9]+) x ([0-9]+)/\1/g')";
-		elif [[ -z "$value" ]] && [[ "x${streamletFields[$i]}" == "xImage height" ]]; then value="$(echo "$streamletInfo" | grep -E 'Image size\s*:\s*[0-9]+ x [0-9]+' | sed -E 's/Image size\s*:\s*([0-9]+) x ([0-9]+)/\2/g')";
-		fi
-
-		# n.b. if file has no exif data, exiv2 exits with error „No Exif data found in the file“ and thus $streamletValid != 0, but there still might be some value like „Image size“
-		if   [[ ! "x$streamletValid" == "x0" ]] && [[ "x$value" == "x" ]]; then value="";  isNull="true";
-		else                                                                               isNull="false";
-		fi
-
-		if ( [[ "x${streamletFields[$i]}" == "xImage height" ]] || [[ "x${streamletFields[$i]}" == "xImage width" ]] ) && [[ ! "$value" =~ ^[0-9]+$ ]]; then value="0"; isNull="true"; fi
-
-		send OUTPUT_ATTRIBUTE "$value"    "$isNull";
-	done
-	
-	send WAITING_FOR_INPUT_ATTRIBUTES;
-}
-
-initialize
-processMessages