#!/usr/bin/env bash

# @(#) s1       Demonstrate executing one script several times simultaneously, parallel.

# Utility functions: print-as-echo, print-line-with-visual-space, debug.
# export PATH="/usr/local/bin:/usr/bin:/bin"
LC_ALL=C ; LANG=C ; export LC_ALL LANG
pe() { for _i;do printf "%s" "$_i";done; printf "\n"; }
pl() { pe;pe "-----" ;pe "$*"; }
em() { pe "$*" >&2 ; }
db() { ( printf " db, ";for _i;do printf "%s" "$_i";done;printf "\n" ) >&2 ; }
db() { : ; }
C=$HOME/bin/context && [ -f $C ] && $C parallel

FILE=${1-data1}

pl " Input data file $FILE:"
cat $FILE

pl " Script to be run in parallel, \"inner\":"
cat inner

pl " Results:"
cat $FILE |
parallel -j4 ./inner {}

exit 0

$ ./s1

Environment: LC_ALL = C, LANG = C
(Versions displayed with local utility "version")
OS, ker|rel, machine: Linux, 3.16.0-4-amd64, x86_64
Distribution        : Debian 8.6 (jessie) 
bash GNU bash 4.3.30
parallel GNU parallel 20130922

-----
 Input data file data1:
a
b
c
d

-----
 Script to be run in parallel, "inner":
#!/usr/bin/env bash

# @(#) inner    Demonstrate one process to be run.

echo " Hello world from $$ with input values" \""$*"\"

exit 0

-----
 Results:
 Hello world from 4452 with input values "a"
 Hello world from 4453 with input values "b"
 Hello world from 4454 with input values "c"
 Hello world from 4455 with input values "d"

parallel -j4 ./inner {}