$2$ Pipeline command

Complete the main function in pipes.c to implement the following pipeline command:

ls $/$dev $|$ xargs $|$ cut $-$d$-$f$-$

where $-$d is followed by a white space within single$-$quotes and and are positive integers

specified as command line arguments of your program.

Let$$s understand what the pipeline command does. It consists of three external commands, which can

take zero or more arguments, chained together to form a single instruction. The $3$ stages of the pipeline

are as follows:

$1.$ The first stage, ls $/$dev$,$ outputs the list of files in $/$dev into a pipe.

$2.$ The second stage, xargs, takes the output of stage $1$ on its standard input, delimits it by

blanks, and sends the output into the second pipe.

$3.$ The third stage, cut $-$d$-$f$-,$ takes the output of stage $2$ as its input and prints

the selected fields $($in the range a to b$)$ on the standard output delimited by a whitespace. Note

that the pair of quotes after $-$d are not needed when passing arguments through execl.

Below are sample outputs from running the program on Github Codespaces. Note that the output may

vary on your local machine. The length of each output, however, should be the same as the below

examples.