Select all of the following statements that are true. Most \"commands\" executed

Question

Select all of the following statements that are true. Most "commands" executed from a Unix shell are actually ordinary Unix programs. Unix command line programs usually accept inputs and produce outputs. The ' ' character redirects the output of a program to a file, and ' > > 'redirects the output of a program to append to a file. The '|' character is called a "pipe" and it is used to redirect the output of a program into the input of another program. Using pipes, many programs can be strung together to accomplish complex tasks. The cat program concatenates all of its inputs to its output. cat file1 file2 file3 > stuff will replace the contents of file1, file2, and file3 with the contents of the file named stuff. Copy and paste the following command and execute it on Thor: cat /usr/share/dict/words | grep -e 'aa. *' | sort-u | wc -| The output of is 399. The cat program reads and outputs the contents of the file/usr/share/dict/words. The grep program searches its input text and outputs only lines from the input that match a specified pattern. (Use man grep to find out). The sort -u command uses the output of grep for input. The wc program uses the output from sort as input and outputs the number of characters in its input. Lookup the -/ option to wc with man wc. McIlroy, then head of the Bell Labs CSRC (Computing Sciences Research Center), and inventor of the Unix pipe, summarized the Unix philosophy as follows: "This is the Unix philosophy: Write programs that do one thing and do it well. Write programs to work together. Write programs to handle text streams, because that is a universal interface. "In a related article published in the January 1971 issue of BYTE magazine, Leaurant Connerie warned hobbyists not to follow any specific computer science philosophy or risk letting the magic smoke escape.

Explanation / Answer

All the statements are true except the following:
  
   The cat program concatenates all of its inputs to its output. cat file1 file2 file3 > stuff will replace the contents of file1, file2, and file3 with the contents of the file named stuff.

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