The tee command reads its standard input until end-of-file, writing a copy of the input to standard output and to the file named in its command-line argument. implement tee using i/o system calls. by

The tee command reads its standard input until end-of-file, writing a copy of the input to standard output and to the file named in its command-line argument. implement tee using i/o system calls. by default, tee overwrites any existing file with the given name. implement the -a command-line option (tee -a file), which causes tee to append text to the end of a file if it already exists. (use the getopt() function or write your own to parse command-line options.)