The spell command collects words from the named files and looks them up in a spelling list. Words that neither occur among nor are derivable (by applying certain inflections, prefixes, or suffixes) from words in the spelling list are written to the standard output.
If there are no file arguments, words to check are collected from the standard input. spell ignores most troff(1), tbl(1), and eqn(1) constructs. Copies of all output words are accumulated in the history file (spellhist), and a stop list filters out misspellings (for example, their=thy-y+ier) that would otherwise pass.
The standard spelling list is based on many sources, and while more haphazard than an ordinary dictionary, is also more effective in respect to proper names and popular technical words. Coverage of the specialized vocabularies of biology, medicine and chemistry is light.
Three programs help maintain and check the hash lists used by spell:
Reads a list of words from the standard input and writes the corresponding nine-digit hash code on the standard output.
Reads n hash codes from the standard input and writes a compressed spelling list on the standard output.
Reads a compressed spelling_list and recreates the nine-digit hash codes for all the words in it. It writes these codes on the standard output.
The following options are supported:
Check British spelling. Besides preferring "centre," "colour," "programme," "speciality," "travelled," and so forth, this option insists upon -ise in words like "standardise."
Follow the chains of all included files.
Print all words not literally in the spelling list, as well as plausible derivations from the words in the spelling list.
Print every plausible stem, one per line, with = preceding each word.
Specify a set of words that are correct spellings (in addition to spell's own spelling list) for each job. local_file is the name of a user-provided file that contains a sorted list of words, one per line. Words found in local_file are removed from spell's output. Use sort(1) to order local_file in ASCII collating sequence. If this ordering is not followed, some entries in local_file may be ignored.
The following operands are supported:
A path name of a text file to check for spelling errors. If no files are named, words are collected from the standard input.
See environ(5) for descriptions of the following environment variables that affect the execution of spell: LC_CTYPE, LC_MESSAGES, and NLSPATH.
hashed spelling lists, American & British
hashed stop list
See attributes(5) for descriptions of the following attributes:
|ATTRIBUTE TYPE||ATTRIBUTE VALUE|
Misspelled words can be monitored by default by setting the H_SPELL variable in /usr/bin/spell to the name of a file that has permission mode 666.
spell works only on English words defined in the U.S. ASCII codeset.
Because copies of all output are accumulated in the spellhist file, spellhist may grow quite large and require purging.
The spelling list's coverage is uneven; new installations may wish to monitor the output for several months to gather local additions.
British spelling was done by an American.