(old)Puppy Linux Discussion Forum

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#using shell builtins to replace long pipes of external commands
#
#while read A || [ "$A" ]; do A=`echo $A`;echo ${A};done <<<"${VAR}" |
#or
#while read A || [ "$A" ]; do A=`echo $A`;echo ${A};done <$FILE |
#can replace:
# echo "${VAR}" |tr "\t" " "|tr -s " "|cut/sed ... |
#or
# cat $FILE |tr "\t" " "|tr -s " "|cut/sed ... |
#
#both tr commands are replaced with VAR=`echo $VAR`
#cut is replace with the second <and third> echo using substring manipulation
#use:
# echo ${A#* * *} to remove the first 3 fields or ${A%* * *} to remove the last 3
#there is another alternative if you no longer need the input parameters
#use:
# set `echo $A`; echo $1,$5,$7 ... this uses the 1st,5th&7th " " separated word
#you can also use the IFS value if you want "|" to separate words
#ex.  OLDIFS="${IFS}";IFS="|";...commands...;IFS="${OLDIFS}"
#sed can often be replaced with thie ${VAR///} substring manipulations
#use:
# echo ${A//"${OLDSTRING}"/"${NEWSTRING}"} as a sed replacement
#NOTE this method will work for multiple lines while sed will not
#NOTE on IFS and read, set etc...
#you can get creative with read and IFS too, but it can get difficult to follow
#normally read uses a new line (represented by \n) as the delimiter
#_some_ shells have -d parameter for read, but for portability set/reset IFS
#be careful though, setting IFS will affect other commands too, for example
#set `echo "a b c d e f"`; echo $1 .... "a b c d e f" when IFS="|" ...oops
#this is a feature, not a bug

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#!/bin/bash
if [[ $1 == *.png ]]
then
/usr/bin/geany 
else
if [[ $1 == *.PNG ]]
then
/usr/bin/geany 
else
if [[ $1 == *.jpeg ]]
then
/usr/bin/geany
else
if [[ $1 == *.jpg ]]
then
/usr/bin/geany
else
if [[ $1 == *.pet ]]
then
/usr/bin/viewnior
else
/usr/bin/mtpaint
fi fi fi fi fi

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#!/bin/bash
if [[ $1 == *.png or *.jpg or *.jpeg or *.PNG ]]
then
do something
else
do something else
fi

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case $1 in
 *.png|*.PNG|*.jpg|*.jpeg) process_pic;;
 *.pet|*.deb|*.rpm) process_pkg;;
 *) do_something_else;;
esac

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rox $@

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#!/bin/sh
MIME=`file -b --mime-type $1`
/root/Choices/MIME-types/${MIME//\//_} $1

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#!/bin/bash
for ((i=1; i<=$#; i++)); do
 case "${!i}" in
  *.pet|*.deb|*.rpm) busybox cp "${!i}" /destination1 &;;
  *.zip|*.rar|*.bz2) busybox cp "${!i}" /destination2 &;;
  *) busybox cp "${!i}" /destination3 &;;
 esac
done

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#!/bin/sh
for i in "$@"; do
 case "${i}" in
  *.pet|*.deb|*.rpm) busybox cp "${i}" /destination1 &;;
  *.zip|*.rar|*.bz2) busybox cp "${i}" /destination2 &;;
  *) busybox cp "${i}" /destination3 &;;
 esac
done

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#!/bin/sh
while [ $# -ne 0 ]; do
 case "$1" in 
  *.pet|*.deb|*.rpm) busybox cp "$1" /dst1 &;; 
  *.zip|*.rar|*.bz2) busybox cp "$1" /dst2 &;; 
  *) busybox cp "$1" /dst3 &;; 
 esac 
 shift
done