DESCRIPT.ION files are files used in BBSen and the programs 4NT and Take Command. These files describe other files in the directory.
Below is a technical summary of the orignal format, plus an extension to the format.
contents = *(file-line) [EOF]
file-line = file-name SP description *(app-specific-tags)
file-name = *VCHAR
description = *(VCHAR / SP)
app-specific-tags = EOT app-id app-desc
app-desc = *(VCHAR / SP)
EOT = %x04 ; ASCII End-Of-Transmission
EOL = CR LF / CR / LF / EOF
EOF = %x1A ; ASCII End-Of-File
The maximum file size for DESCIPT.ION files is 4096 bytes.
DESCRIPT.ION files (or .descript.ion files in UNIX style OSen) can break some limitations with the following format.
contents = header EOL *(file-line)
header = content-name SP "DESCRIPT.ION" SP "RW" [*(SP extension)]
extension = name [":" value]
file-line = file-name HTAB *SP description *(HTAB tag)
file-name = *(VCHAR / SP)
description = *(VCHAR / SP)
tag = name ":" *SP value
name = *(ALPHA / DIGIT / "-" / "_" )
value = *(VCHAR / SP)
EOL = CR LF / CR / LF
File size is constraigned only by operating system file size limits. File names may be further constraigned by the operating system and/or file system.
A basic example:
.descript.ion DESCRIPT.ION RW
foo.bar test file type:junk
Extensions may also be specified in the header. For example, if an index extenstion were to be developed:
.descript.ion DESCRIPT.ION RW index:.desc.idx