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Question 1

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Answer 1

Translate, squeeze, and/or delete characters from standard input, writing to standard output.

Question 2

tr [OPTIONS]

• c
• d
• s
• t

Answer 2

• c, -C, –complement, Use the complement of SET1
• d, –delete, Delete characters in SET1, do not translate.
• s, –squeeze-repeats, Replace each sequence of a repeated character that is listed in the last specified SET, with a single occurance of that character.
• t, –truncate-set1, First truncate SET1 to length of SET2.

Question 3

tr [SET OPTIONS]

\ backslash

\a audible BEL

\b backspace

\f form feed

\n newline

\r return

\t horizontal tab

\v vertical tab

CHAR1-CHAR2 all characters from CHAR1 to CHAR2 in ascending order.

Answer 3

[CHAR*] In SET2, copies of CHAR until length of SET1

[CHAR*REPEAT] REPEAT copies of CHAR, REPEAT octal if starting with 0

[:alnum:] all letters and digits

[:alpha:] all letters

[:blank:] all horizontal whitespace

[:cntrl:] all control characters

[:digit:] all digits

[:graph:] all printable characters, not including space

[:lower:] all lower case letters

[:print:] all printable characters, including space

[:punct:] all punctuation characters

[:space:] all horizontal and vertical whitespace

[:upper:] all upper case letters

[:xdigit:] all hexadecimal digits

[=CHAR=] all characters which are equivalent to CHAR