Chapter 16. Spell Checking, Word Counting, and Textual Analysis

The Unix spell Command

On some Unix systems, the spell command reads one or more files and prints a list of words that may be misspelled. You can redirect the output to a file, use grep (Section 13.1) to locate each of the words, and then use vi or ex to make the edits. It’s also possible to hack up a shell and sed script that interactively displays the misspellings and fixes them on command, but realistically, this is too tedious for most users. (The ispell (Section 16.2) program solves many — though not all — of these problems.)

When you run spell on a file, the list of words it produces usually includes a number of legitimate words or terms that the program does not recognize. spell is case sensitive; it’s happy with Aaron but complains about aaron. You must cull out the proper nouns and other words spell doesn’t know about to arrive at a list of true misspellings. For instance, look at the results on this sample sentence:

$ cat sample
Alcuin uses TranScript to convert ditroff into
PostScript output for the LaserWriter printerr.
$ spell sample
Alcuin
ditroff
printerr
LaserWriter
PostScript
TranScript

Only one word in this list is actually misspelled.

On many Unix systems, you can supply a local dictionary file so that spell recognizes special words and terms specific to your site or application. After you have run spell and looked through the word list, you can create a file containing the words that were not actual ...

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