The gscan utility scans a GDSII file and reports on the list of structures, hierarchy, data with layers, extents of each structure and number of elements in each structure. The results from gscan can be used for a variety of purposes.
GSCAN Command Line Syntax
To see the gscan command line syntax you can execute gscan with the -h option:
$ gscan -h GDSII Scanning Utility Version 1.47 (Oct 11,2002) (C) 1993-2001 Artwork Conversion Software, Inc. gscan [input_gdsii_file_name] [options] options -o:output_file_name name/path of the output file. If not specified goes to stdout -sh output structure hierarchy -sea output structure extents for all structures -byarea output structure extents sorted by area -se:structure_name output structure extents for this structure only -job output job file only -job:job_filename output job file to job_filename only -job! output job file -job!job_filename output job file to job_filename -dtp include datatype info on output -max:N expect at most N structures. ( default 2048 ) -magic enable magic compatibility. -elmcnt output element counts for each structure.
GSCAN outputs ASCII data about a file. Examples of the various options are shown below. Because of the large amount of data the example output is "clipped."
Basic Header InformationGSCAN always writes out some basic information obtained from the header data in the GDSII file.
FILENAME DEMO5.GDS HEADER Release :3.00 release version Last Modify Time :Sep 9, 93 at 0:00:00 Last Access Time :Sep 9, 93 at 0:00:00 Resolution :1000 ticks per user unit User Units :UM Reference Library 1) 2) Text Font Definition Files 0) GDSII:CALMAFONT.TX font path - not really helpful 1) GDSII:CALMAFONT.TX 2) GDSII:CALMAFONT.TX 3) GDSII:CALMAFONT.TX
Layers with Data
GSCAN also produces a list of the layers in the GDSII file that contain data.
gscan demo5.gds -o:test.txt -sh
In addition to basic header information you also get a list of structures and then the hierarchy.
STRUCTURE_LIST 1) HVLS 2) CONT 3) PTAP2 4) POLYHD1 5) POLYHD3 6) CMP2 7) NTAP 8) PTAP 9) POLYHD2 10) HVPD 11) SVCMPIN 12) TGX1 . . HIERARCHY of INDEPENDENT STRUCTURES 1988 TOP | |__ INPROT3 | | | |__ CONT | | | |__ PAD | |__ INGATE2 | | | |__ PTAP2 | | | |__ CONT | | | |__ POLYHD3 | | | | | |__ CONT | | | |__ POLYHD1