Command Files

A command file (also called a session file) is an INI-format text file with a .lsn extension that sets any combination of LinkCAD options. Command files are used to share settings between machines, automate repetitive conversions, and restore saved sessions.

File Format

Command files use the standard INI format with a required [LinkCAD] section header:

[LinkCAD]
LcImportFormat=GDSII
LcExportFormat=DXF
LcImportFile=C:\designs\chip.gds
LcExportFile=C:\output\chip.dxf

Syntax Rules

• The [LinkCAD] section header is required (case-insensitive)
• Lines before the section header are ignored
• Each option is on its own line: OptionName=value
• Values may be quoted: LcImportFile="C:\path with spaces\file.gds"
• Whitespace around = and around values is trimmed
• Empty values are ignored

ToolApply

Multiple ToolApply lines are allowed and are concatenated with ; separators:

[LinkCAD]
ToolApply=Merge
ToolApply=SanitizePolygons

This is equivalent to:

[LinkCAD]
ToolApply=Merge;SanitizePolygons

Using Command Files

From the GUI

• File → Load Session (Ctrl+O) loads a .lsn file and applies all its options
• File → Save Session (Ctrl+S) writes the current options to a .lsn file

From the Command Line

linkcad.exe --config my_settings.lsn --console --quit

Options passed on the command line take precedence over values in the command file. This lets you use a command file for shared settings while overriding specific values per invocation:

linkcad.exe --config gds_to_dxf.lsn `
    --import chip_a.gds --export chip_a.dxf --quit

Common Options

Core Options

Option	Type	Description
LcImportFile	string	Input file path
LcExportFile	string	Output file path
LcImportFormat	string	Import format name (e.g. GDSII, DXF)
LcExportFormat	string	Export format name (e.g. DXF, CIF)
LcConvertBatch	boolean	Enable batch conversion mode
LcBatchCombineFiles	boolean	Combine multiple files into single output
LcApplyLayerMap	boolean	Apply layer map during conversion
ToolApply	string	Tools to apply (semicolon-separated)

DXF Options (examples)

Option	Type	Description
DxfOutScaling	real	Output scaling factor
DxfOutBinary	boolean	Write binary DXF
DxfOutFormatVersion	string	DXF version (e.g. 2000)
DxfInScaling	real	Import scaling factor
DxfInExplodeSplines	boolean	Convert splines to polylines
DxfInKeepClosedZeroWidthPolylinesAsPolylines	boolean	Keep valid closed zero-width DXF polylines as polylines

Tool Options (examples)

Option	Type	Description
ToolArcPrecValue	integer	Arc/curve approximation precision value
ToolArcPrecUnits	integer	Precision mode: -1 = segments/360°, otherwise a unit enum
ToolConvertZeroWidthClosedPolylines	boolean	Convert closed zero-width polylines to polygons in Convert to Outline / Explode to Polygons
ToolDontExplode	boolean	Merge Shapes option Only merge polygons; legacy label: Don’t explode complex shapes
ToolHolesModeOmitLink	boolean	Hole mode Extract holes as polygons; legacy label: Omit cut-lines in re-entrant polygons. See Merge Hole Output Modes

GDSII Options (examples)

Option	Type	Description
GdsOutDbScalingUnits	integer	Database units
GdsOutDbScalingValue	real	Database scaling value
GdsInIgnoreText	boolean	Skip text elements on import

Gerber Options (examples)

Option	Type	Description
GbrInUnits	integer	Import units
GbrOutDecimals	integer	Output decimal places
GbrOutAbsCoordinate	boolean	Use absolute coordinates

Tip

Run linkcad.exe --help-all to see the complete list of all available options.

Example: GDS to DXF Conversion

[LinkCAD]
LcLoadDefaults=true
LcImportFormat=GDSII
LcExportFormat=DXF
LcImportFile=C:\designs\chip.gds
LcExportFile=C:\output\chip.dxf
DxfOutScaling=1000
DxfOutFormatVersion=2000
ToolApply=SanitizePolygons

Example: Gerber Import with Tools

[LinkCAD]
LcLoadDefaults=true
LcImportFormat=Gerber RS-274X
LcExportFormat=GDSII
GbrInUnits=4
ToolApply=Merge
ToolApply=Deembed

How Sessions Relate to Command Files

Session files and command files use the same .lsn format. When you save a session in the GUI, LinkCAD writes all currently recorded options to the file. When you load a session or use --config, LinkCAD reads the file using the same INI parser. See Sessions for more about session management.