Inline helper to simplify usage.

parallel_parse.sh

-#!/bin/sh
+#!/bin/bash
 usage() {
   echo "Usage:"
   echo "  find [...] -print0 | $0 \\"
-  echo "    path_to_helper parallelism state_dir out_file command [arg1 [...]]"
+  echo "    parallelism state_dir out_file command [arg1 [...]]"
   echo "Reads filenames to process from stdin, null-delimited."
 }
 
@@ -11,12 +11,6 @@ if [ $1 = '-h' -o $1 = '--help' ]; then
   exit 0
 fi
 
-HELPER=$1
-if [ ! -x "$HELPER" ]; then
-  echo "$HELPER cannot be executed"
-  exit 1
-fi
-shift
 PARALLELISM=$1
 shift
 STATE_DIR=$1
@@ -30,5 +24,6 @@ if [ $# -eq 0 ]; then
   exit 1
 fi
 
-xargs -0 -r -n 1 -P $PARALLELISM -I "@FILE@" "$HELPER" "@FILE@" "$STATE_DIR" "$@"
+# XXX: any simpler way ?
+xargs -0 -r -n 1 -P $PARALLELISM -I "@FILE@" -- "$SHELL" -c 'INFILE="$1";shift;STATE_DIR="$1";shift;echo -n .;"$@" -Q --format json --out "$STATE_DIR/$(sed s:/:@:g <<< "$INFILE").json" "$INFILE"' "$0" "@FILE@" "$STATE_DIR" "$@"
 "$@" --out "$OUT_FILE" --state-file "$STATE_DIR"/*

parallel_parse_helper.sh

-#!/bin/bash
-INFILE=$1
-shift
-STATE_DIR=$1
-shift
-echo -n '.'
-exec "$@" -Q --format json --out "$STATE_DIR/$(sed s:/:@:g <<< "$INFILE").json" "$INFILE"