:
##########################################################################
# Title      :	grepcat - "grep" and "cat" file (instead of line)
# Author     :	Heiner Steven <heiner.steven@odn.de>
# Date       :	2003-11-19
# Requires   :	grep
# Category   :	File Utilities
# SCCS-Id.   :	@(#) grepcat	1.2 04/02/09
##########################################################################
# Description
#    o	"grepcat" searches like "grep" for patterns in a file. In
#	contrast to "grep" it will print the contents of the whole file
#	in case of a match.  "grep" would only print the lines matching
#	the pattern.
#    o	"grepcat -v pattern " will return success if the input does not
#	contain the specified pattern. Note that this is different from
#	"grep -v pattern", which will return successfully if there is at
#	least one line not matching the pattern.
# Examples:
#	# Print the output of a command only when it contains a certain
#	# keyword, but print the whole output in that case:
#	checksomething | grepcat -i 'error'
##########################################################################

PN=`basename "$0"`			# Program name
VER='1.2'

: ${GREP:=egrep}

usage () {
    echo >&2 "$PN - \"$GREP\" and \"cat\" file (instead of line), $VER
usage: $PN [-ilv] regexp [file ...]
    -i:  ignore case
    -l:  list file name (instead of the file's contents)
    -v:  inverse sense of search: find files NOT containing pattern

Like \"$GREP\" $PN will search the file(s) for the specified regular
expression. However, if a line matches, it will print the whole file
instead of just the matching line."
    exit 1
}

msg () {
    echo >&2 "$PN:" "$@"
}

fatal () { msg "$@"; exit 1; }

##########################################################################

ListNames=false
Invert=false
grepflags=
while getopts :hilv opt
do
    case "$opt" in
    	i)	grepflags="${grepflags+$grepflags }-i";;
	v)	Invert=true;;
	l)	ListNames=true;;
	*)	usage;;
    esac
done
shift `expr $OPTIND - 1`

: '
# Uncomment the following lines if your shell does not have a "getopts"
# command.
set -- `getopt :hilv "$@"` || usage
[ $# -lt 1 ] && usage			# "getopt" detected an error

ListNames=false
Invert=false
grepflags=
while [ $# -gt 0 ]
do
    case "$1" in
    	-i)	grepflags="${grepflags+$grepflags }-i";;
	-v)	Invert=true;;
	-l)	ListNames=true;;
	--)	shift; break;;
	-h)	usage;;
	-*)	usage;;
	*)	break;;			# First file name
    esac
    shift
done
'

[ $# -lt 1 ] && usage
Search=$1; shift

# Special handling: if we should only list names, and "-v" was not specified,
# we'll work like "grep -l":

if [ $ListNames = true ] && [ $Invert = false ]
then
    #echo >&2 "DEBUG: using command: $GREP -l $grepflags $Search [files ...]"
    exec $GREP -l $grepflags "$Search" "$@"
fi

# Define what exit code of "grep" means "success". Usually this is when
# the pattern was found, but "-v" reverses the meaning.

if $Invert
then success=1
else success=0
fi

result=1
if [ $# -lt 1 ]
then
    tmp=${TMPDIR:=/tmp}/mg.$$
    trap 'rm -f "$tmp"' 0
    trap "exit 2" 1 2 3 13 15

    umask 0077
    (> "$tmp") ||
	fatal "cannot create temporary file: $tmp"

    tee "$tmp" | $GREP $grepflags "$Search" >/dev/null
    if [ $? -eq $success ]
    then
    	if $ListNames
	then echo "STDIN"
	else cat "$tmp"
	fi
	result=0
    fi
else
    for file
    do
    	$GREP $grepflags "$Search" "$file" >/dev/null
	if [ $? -eq $success ]
	then
	    if $ListNames
	    then echo "$file"
	    else cat "$file"
	    fi
	    result=0
	fi
    done
fi
exit $result