Need unix command file HELP!

[Geoff Kuenning]

In article <259 at hadron.UUCP> jsdy at hadron.UUCP (Joseph S. D. Yao) writes:

> 	text=`file "$file" | grep text`

Actually, there's still a gotcha here:  it will pick up files named
'text.o', 'context.o', etc. (I know this from painful experience!).  A
better way to detect text files is:

	text=`file "$file" | grep ':.* text'`

or even
	text=`file "$file" | grep 'text$'`

but I'd use the last only after checking the source of /bin/file to make
sure it always put 'text' last on the line.

Anyway, here is a TESTED (what a radical idea) shell script that:
(1) Searches only text files (2) Accepts the -l and -n switches of 'grep'
(3) remembers to put in /dev/null if -l is not specified, and (4) uses
xargs if it is available in /bin or /usr/bin.  Both the BSD and the
System V variants have been tested (it adapts dynamically).  It is an
improved version of a script that I sent to the original question-asker
more than a month ago.

Now, can we *please* move on to a new subject?

	Geoff Kuenning
	{hplabs,ihnp4}!trwrb!desint!geoff
------------------------cut here--------------------------
: Use /bin/sh
#!/bin/sh
#
#	Locate a string in any (text) file, anywhere in the system.
#
#	Usage:
#
#	findstring [-l] [-n] [-g grep-program] [root-directory] search-string
#
#	If the search-string contains semicolons, they should be backslashed,
#	thus:
#
#	findstring "break\;"
#
#	The -l and -n switches are passed to the 'grep' program.
#
#	The -g switch selects a different grep program;  the default is 'grep'.
#
#	WARNING:  this command is very slow, and loads down the system
#	quite heavily.  The System V version opens every file in the
#	system;  the BSD version does that and also spawns at least one
#	process for every file in the system and another for every
#	text file.  You can reduce the system load by a little bit by
#	initiating the command from the root directory.
#
#	Note:  this is written to be portable to System V and BSD.  It
#	has only been tested on system V, though the BSD code was also
#	tested there.
#
PATH=/bin:/usr/bin
ROOTDIR=/
grepargs=
nullfile=/dev/null
grep=grep
while :
do
    case "X$1" in
	X-l)
	    grepargs="$grepargs -l"
	    nullfile=
	    shift
	    ;;
	X-n)
	    grepargs="$grepargs -n"
	    shift
	    ;;
	X-g)
	    grep=$2
	    shift; shift
	    ;;
	X-*)
	    set illegal arguments - this will cause a message
	    break
	    ;;
	*)
	    break
	    ;;
    esac
done
if [ $# -gt 1 ]
then
    ROOTDIR=$1
    shift
fi
if [ $# -ne 1 ]
then
    echo 'Usage:  findstring [-l] [-n] [-g grep-program]' \
      '[root-directory] search-string' 1>&2
    exit 2
fi
#
#	If you have UniSoft System V, test xargs to see if it has a bug by
#	typing:
#
#	    echo a b c | xargs echo
#
#	If you get nothing back, you have the bug.  If you get "a b c",
#	you don't.
#
#	If you have the bug, you will have to disable the xargs variant
#	below and make it run the non-xargs version.  This is unfortunately
#	*much* slower.
#
if [ -x /bin/xargs -o -x /usr/bin/xargs ]
then
    #
    #	The system has xargs; use it
    #
    find $ROOTDIR -type f -print \
      | xargs file \
      | sed -n '/:	.* text/s/:	.*$//p' \
      | xargs $grep $grepargs "$1" $nullfile
else
    #
    #	Too bad, there's no xargs.  We'll have to do it the hard way.
    #
    find $ROOTDIR -type f -exec file {} \; \
      | sed -n '/:	.* text/{
	  s/:	.*$//
	  s;^;'"$grep $grepargs '$1' $nullfile"' ;p
	  }' \
      | sh
fi
#
# Unfortunately, the grep's will return a nonzero status if they find
# nothing, so there isn't much point in returning their status.
#
exit 0