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Full Discussion: Using awk to read a specific line and a specific field on that line.
Top Forums Shell Programming and Scripting Using awk to read a specific line and a specific field on that line. Post 302543390 by agama on Sunday 31st of July 2011 01:13:43 PM
Old 07-31-2011
Quote:
Originally Posted by Bungkai

Code:
sed -i "s/$searchName\ $2/$name\ $lname/g" database.txt

This works for me assuming that searchName == John, $2 == Wall. If you've invoked your script with just John on the command line, $2 will be null, then you'll end up with the results that you posted. The small script I wrote to test your code includes some error checking that might be beneficial in your case so I've posted it as an example.

Code:
#!/usr/bin/env ksh

if [[ $# != 4 ]]
then
   echo "error: missing parms. expected:  name lastname newname new-lastname"
   exit 1
fi
searchName=$1
# $2 is not assigned and used directly later 
name=$3
lname=$4

sed  "s/$searchName\ $2/$name\ $lname/g" test.data

I would recommend assigning $2 to a named variable; while it is fine the way it is, it makes your script easier to read if it were something like this:

Code:
sed  "s/$searchName\ $searchLastname/$name\ $lname/g" test.data

I also don't believe that you need to escape the spaces. This should work:
Code:
sed  "s/$searchName $2/$name $lname/g" test.data

and again makes the code easier to read.

---------- Post updated at 13:13 ---------- Previous update was at 13:10 ----------

Thought I would also note that I dropped the -i from my testing because the version of sed that I prefer does not implement it. It should work just fine if you prefer to use that option.
 

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LEARN ABOUT DEBIAN

ogrtindex

ogrtindex(1)						      General Commands Manual						      ogrtindex(1)

NAME

       ogrtindex - ogrtindex creates a tileindex

SYNOPSIS

       ogrtindex [-lnum n]... [-lname name]... [-f output_format]
		 [-write_absolute_path] [-skip_different_projection]
			output_dataset src_dataset...

DESCRIPTION

       The ogrtindex program can be used to create a tileindex - a file containing a list of the identities of a bunch of other files along with
       there spatial extents. This is primarily intended to be used with MapServer for tiled access to layers using the OGR connection type.

       -lnum n:
	   Add layer number 'n' from each source file in the tile index.

       -lname name:
	   Add the layer named 'name' from each source file in the tile index.

       -f output_format:
	   Select an output format name. The default is to create a shapefile.

       -tileindex field_name:
	   The name to use for the dataset name. Defaults to LOCATION.

       -write_absolute_path:
	   Filenames are written with absolute paths

       -skip_different_projection:
	   Only layers with same projection ref as layers already inserted in the tileindex will be inserted.

       If no -lnum or -lname arguments are given it is assumed that all layers in source datasets should be added to the tile index as independent
       records.

       If the tile index already exists it will be appended to, otherwise it will be created.

       It is a flaw of the current ogrtindex program that no attempt is made to copy the coordinate system definition from the source datasets to
       the tile index (as is expected by MapServer when PROJECTION AUTO is in use).

EXAMPLE

       This example would create a shapefile (tindex.shp) containing a tile index of the BL2000_LINK layers in all the NTF files in the wrk
       directory:

       % ogrtindex tindex.shp wrk/*.NTF

AUTHORS

       Frank Warmerdam warmerdam@pobox.com, Silke Reimer silke@intevation.de

GDAL
								  Tue Sep 18 2012						      ogrtindex(1)
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