= The `ogrinfo` utility =
  ''The official documentation for the `ogrinfo` utility is http://www.gdal.org/ogr/ogrinfo.html''

== -so Summary Only ==
  ''supress listing of features, show only the summary information like projection, schema, feature count and extents.''

To get this info with shapefiles you must also provide the ``layer`` name, else not much useful is returned:
{{{
$ ogrinfo -so contours.shp

INFO: Open of `contours.shp'
  using driver `ESRI Shapefile' successful.
1: contours (Line String)
}}}

Likely what is really wanted is:

{{{
$ ogrinfo -so contours.shp contours

INFO: Open of `contours.shp'
      using driver `ESRI Shapefile' successful.

Layer name: contours
Geometry: Line String
Feature Count: 3393
Extent: (57537.995662, 663561.802226) - (88297.082026, 694443.881449)
Layer SRS WKT:
PROJCS["Albers",
...etc.
}}}

Alternatively, use the `-al` switch to see information on all layers. 

== Adding a column through SQL ==

Using ogrinfo is it possible to use SQL language to add a column to an input file.

The SQL syntax is a standard `ALTER TABLE` statement; it's necessary to add `-sql` switch. In example

{{{
$ ogrinfo input.shp -sql "ALTER TABLE input ADD fieldX float"

INFO: Open of `input.shp'
      using driver `ESRI Shapefile' successful.
}}}

In [[https://trac.osgeo.org/gdal/attachment/wiki/UserDocs/OgrInfo/ogrinfo_sql.zip|this]] zip file there are two files to test this command: an input file ("input.shp") and "input_AfterOgrinfo.shp", that is what "input.shp" becomes after ogrinfo command.