# $File: dif,v 1.1 2020/04/09 19:14:01 christos Exp $

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# $File: dif,v 1.1 2020/04/09 19:14:01 christos Exp $
# dif: file(1) magic for DIF text files

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# From: Joerg Jenderek
# URL: http://en.wikipedia.org/wiki/Data_Interchange_Format
# http://fileformats.archiveteam.org/wiki/Data_Interchange_Format
# Note: called by TrID "Data Interchange Format",
# by DROID x-fmt/368 "VisiCalc Database"
0 string TABLE
# skip text starting with TABLE by looking for numeric version on 2nd line
>6 search/2 0,
# skip DROID x-fmt-41-signature-id-380.dif by looking for key word TUPLES at the beginning
>>27 search/128 TUPLES Data Interchange Format
# https://www.pcmatic.com/company/libraries/fileextension/detail.asp?ext=dif.html
#!:mime application/x-dif-spreadsheet Gnumeric
# https://github.com/LibreOffice/online/blob/master/discovery.xml
#!:mime application/x-dif-document LibreOffice
# https://www.wikidata.org/wiki/Wikidata:WikiProject_Informatics/File_formats/Lists/File_formats
!:mime application/x-dif
# https://extension.nirsoft.net/dif
#!:mime application/vnd.ms-excel
#!:mime text/plain
!:ext dif
# look for double quote 0x22 on 3rd line
>>>10 search/3 "
# skip if next character also double quote
>>>>&0 ubyte !0x22 \b, generator or table name
# comment like EXCEL, pwm enclosed in double quotes
>>>>>&-2 string x %s