Write a Perl program to address the following:

It creates a file and writes the integer zero to the file.

The program then calls a fork to spawn a child process. The parent and child processes alternate incrementing a counter in the file. Each time the counter is incremented, print to the console which process, parent or child, is performing the increment.

Each process should tell the other process when it has finished its operation. Each process should wait for the other to complete before incrementing the counter.

The maximum value to which the counter can be incremented is taken as an input from the user. Discuss any challenges that you have faced in writing your program.