fontlint¶
A program for checking the validity of fonts
fontlint fontfile1 ...
fontlint checks a font for certain standard problems
It will notice:
- Any glyphs with intersecting (or self-intersecting) contours. 
- Any contours drawn in the wrong orientation 
- Any glyphs with a flipped reference 
- Missing points at extrema. 
For sfd fonts it will also notice:
- Any open contours (more an issue in sfd files than in released fonts) 
- Adjacent points too far apart in a glyph 
- Unknown glyph referenced in GSUB/GPOS/MATH 
For PostScript fonts it will also notice:
- More points in a glyph than allowed by PostScript. 
- Too many hints in a glyph. 
- Invalid glyph name. 
- Missing BlueValues entry in PostScript Private dictionary 
- Odd number of elements in either the BlueValues or OtherBlues entries in the PostScript Private dictionary. 
- Disordered elements in either the BlueValues or OtherBlues entries in the PostScript Private dictionary. 
- Too many elements in either the BlueValues or OtherBlues entries in the PostScript Private dictionary. 
- Elements too close in either the BlueValues or OtherBlues entries in the PostScript Private dictionary (must be at least 2*BlueFuzz+1 apart). 
- Non-integral elements in either the BlueValues or OtherBlues entries in the PostScript Private dictionary. 
- Alignment zone height in either the BlueValues or OtherBlues is too big for the BlueScale in the PostScript Private dictionary. 
- Odd number of elements in either the FamilyBlues or FamilyOtherBlues entries in the PostScript Private dictionary. 
- Disordered elements in either the FamilyBlues or FamilyOtherBlues entries in the PostScript Private dictionary. 
- Too many elements in either the FamilyBlues or FamilyOtherBlues entries in the PostScript Private dictionary. 
- Elements too close in either the FamilyBlues or FamilyOtherBlues entries in the PostScript Private dictionary (must be at least 2*BlueFuzz+1 apart). 
- Non-integral elements in either the FamilyBlues or FamilyOtherBlues entries in the PostScript Private dictionary. 
- Alignment zone height in either the FamilyBlues or FamilyOtherBlues is too big for the BlueScale in the PostScript Private dictionary. 
- Bad BlueFuzz entry in PostScript Private dictionary. 
- Bad BlueScale entry in PostScript Private dictionary. 
- Bad StdHW entry in PostScript Private dictionary. 
- Bad StdVW entry in PostScript Private dictionary. 
- Bad StemSnapH entry in PostScript Private dictionary. 
- Bad StemSnapV entry in PostScript Private dictionary. 
- StemSnapH does not contain StdHW value in PostScript Private dictionary. 
- StemSnapV does not contain StdVW value in PostScript Private dictionary. 
- Bad BlueShift entry in PostScript Private dictionary. 
- Bad ‘CFF ‘ table. 
For TrueType fonts it will also notice:
- More points in a glyph than specified in ‘maxp’ 
- More paths in a glyph than specified in ‘maxp’ 
- More points in a composite glyph than specified in ‘maxp’ 
- More paths in a composite glyph than specified in ‘maxp’ 
- Instructions longer than allowed in ‘maxp’ 
- More references in a glyph than specified in ‘maxp’ 
- References nested more deeply than specified in ‘maxp’ 
- Bad ‘glyf’ or ‘loca’ table 
In any sfnt (True or OpenType font):
- Bad sfnt table header, bad file/table checksums, overlapping tables, standard tables with incorrect lengths, etc. 
- Bad PostScript fontname entry in the ‘name’ table 
- Bad ‘hhea’, ‘hmtx’, ‘vhea’ or ‘vmtx’ table 
- Bad ‘cmap’ table 
- Bad ‘EBDT’, ‘bdat’, ‘EBLC’ or ‘bloc’ (embedded bitmap) table 
- Bad Apple GX advanced typography table 
- Bad OpenType advanced typography table 
- Bad version number in OS/2 table (must be >0, and must be >1 for OT-CFF fonts)