> tr -cs "[:alpha:]" "\n" < file1
With n = 11 makes:
TR FreeBSD General Commands Manual TR NAME tr
translate characters SYNOPSIS tr csu string string
tr cu d string tr cu s string tr cu
ds string string DESCRIPTION The tr utility copies the
standard input to the standard output with sub
stitution or deletion of selected characters
The following options are available c Complements
the set of characters in string that is c
ab includes every character except for a and
b d The d option causes characters to be
deleted from the input s The s option squeezes
multiple occurrences of the characters listed in
the last operand either string or string in the in
put into a single instance of the character
This occurs after all deletion and translation is
completed u The u option guarantees that any
output is unbuffered In the first synopsis form
the characters in string are translated into the
characters in string where the first character in
string is trans lated into the first character in
string and so on If string is longer than string
the last character found in string is duplicated
until string is exhausted In the second synopsis
form the characters in string are deleted from the
input In the third synopsis form the characters
in string are compressed as described for the
s option In the fourth synopsis form the charact
ers in string are deleted from the input and the
characters in string are compressed as described
for the s option The following conventions can
be used in string and string to specify sets of
characters character Any character not described
by one of the following conven tions represents
itself octal A backslash followed by or octal
digits represents a character with that encoded value
To follow an octal se quence with a digit as
a character left zero pad the octal sequence
to the full octal digits character A backslash
followed by certain special characters maps to special
values a alert character b backspace f form
feed n newline r carriage return t tab v
vertical tab A backslash followed by any
other character maps to that char acter c c
Represents the range of characters between the range
end points inclusively class Represents all characters
belonging to the defined character class Class names
are alnum alphanumeric characters alpha alphabetic charact
ers cntrl control characters digit numeric characters graph
graphic characters lower lower case alphabetic characters
print printable characters punct punctuation characters
space space characters upper upper case characters xdigit
hexadecimal characters With the exception of the
upper and lower classes characters in the classes are
in unspecified order In the upper and lower classes
characters are entered in as cending order For specifi
c information as to which ASCII characters are
in cluded in these classes see ctype and related manual
pages equiv Represents all characters or collating
sorting elements be longing to the same equivalence
class as equiv If there is a secondary orderin
g within the equivalence class the charac ters are
ordered in ascending sequence Otherwise they are
ordered after their encoded values An example of an equiva
lence class might be c and ch in Spanish English
has no equivalence classes n Represents n repeate
d occurrences of the character represented by
This expression is only valid when it occurs in
string If n is omitted or is zero it is
be interpreted as large enough to extend string sequenc
e to the length of string If n has a
leading zero it is interpreted as an octal value
otherwise it s interpreted as a decimal value
The tr utility exits on success and if an error
occurs EXAMPLES The following examples are shown
as given to the shell Create a list of the
words in file one per line where a word is
taken to be a maximal string of letters tr cs
alpha n file Translate the contents of file
to upper case tr lower upper file Strip out non
printable characters from file tr cd print file
COMPATIBILITY System V has historically implemented charact
er ranges using the syntax c c instead of the
c c used by historic BSD implementations and
standardized by POSIX System V shell scripts should work
under this im plementation as long as the range
is intended to map in another range i e
the command tr a z A Z will work as
it will map the character in string to the
character in string However if the shell script is
deleting or squeezing characters as in the
command tr d a z the characters and will
be included in the dele tion or compression
list which would not have happened under an histori
c System V implementation Additionally any scripts that
depended on the sequence a z to represe
nt the three characters a and z will have
to be rewritten as a z The tr utility
has historically not permitted the manipulation of
NUL bytes in its input and additionally stripped
NUL s from its input stream This implementation has
removed this behavior as a bug The tr utility
has historically been extremely forgiving of syntax
er rors for example the c and s options were
ignored unless two strings were specified This implementation
will not permit illegal syntax STANDARDS The tr utility
is expected to be IEEE Std POSIX compatible
It should be noted that the feature wherein the last
character of string is duplicated if string has
less characters than string is permitted by POSIX
but is not required Shell scripts attempting to
be portable to other POSIX systems should use the
convention instead of relying on this behavior The
u option is an extension to the IEEE Std
POSIX standard BSD October
