ftwhich - fault tolerant search for a command name
ftwhich [-#hIp][-t#] program_name
ftwhich is a fault tolerant version of the which(1) command. ftwhich
searches for a given program in all directories included in your PATH
environment variable and reports all files with a name that
approximately matches the given program_name.
ftwhich achieves fault tolerance by calculating the so called
Weighted Levenshtein Distance. The Levenshtein Distance is defined as
the minimum number of character insertions, deletions and
replacements that transform a string A into a string B.
ftwhich is similar to the which command with the following differences:
- ftwhich is by default NOT case sensitive
- ftwhich is fault tolerant
- Some shells have a build in which command that will also search
aliases. ftwhich can naturally not search for aliases as it
does not know about alias definitions.
- ftwhich lists all files that approximately match. The files
first shown take preference over files of the same name printed
later as they are from directories listed earlier in the PATH.
- The level of fault tolerance can be adjusted by specifying the
optional parameter tolerance. A tolerance of 0 specifies exact
-h Prints help/usage information.
-I Do case sensitive search (default is case in-sensitive)
-p print the actual distance value in front of the found filename.
This value is equal to the number of insertions, deletions and
replacements necessary to transform the name of the found
program into the search key.
-# or -t#
Set the fault tolerance level to #. The fault tolerance level
is an integer in the range 0-255. It specifies the maximum
number of errors permitted in finding the approximate match. The
default tolerance is (strlen(searchpattern) - number of
wildcards)/6 + 1
The program file to search for. ’*’ and ’?’ can be used as
’?’ denotes one single character.
’*’ denotes an arbitrary number of characters.
The last argument to ftwhich is not parsed for options as the program
needs at least one program_name argument. This means that ftwhich -x
will not complain about a wrong option but search for the program named
Search for all programs like gcc in your PATH:
This will e.g. find gcc or cc or CC ...
To find all files that start with any prefix and end in config and
differ in 2 letters from the word config:
ftwhich -2 ’*config’
To find all files that exactly start with the prefix if:
ftwhich -0 ’if*’
To find all clock programs:
ftwhich -0 *clock*
The wildcards ’?’ and ’*’ can not be escaped. These characters
function always as wildcards. This is however not a big problem since
there is normally hardly any command that has these characters in its
Guido Socher (firstname.lastname@example.org)