That was a very clear and concise explanation, thank you again.

and this:

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makes a lot of sense. I had to read it a few times but I definitely see what you mean and why you say it. Thanks.

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OK, so I increased the size of the array and modified the user input part to look like this:

printf("Enter Desired Operation: ");
fgets(conversion, sizeof(conversion), stdin);
conversion[strlen(conversion) -1] = '\0';

and everything works like I want it to. But I am confused as to why 4 is not large enough array. I thought that the string had one end of line character at the end. So is there and end of line AND end of string character? Also you said:

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and I'm not sure what you mean by that. I should disclose that I am VERY new to this. I picked up the book "Practical C Programming" and this program is an exercise at the end of chapter 7. So everything from chapter 1 until now is the extent of my knowledge. I will be very grateful for any further explanation or advice, I'm really trying to soak up as much as possible. Thanks for your help.

If I were in your position and I wanted to know if my remote machine was on but didn't want to rely on a piece of software running to accomplish it I would simply set my firewall to "REJECT" packets on a firewalled port instead of "DROP"

This way you could use something like nmap to determine if your machine is on by:

nmap -sS [Remote IP] -p[random port]

and if the result comes back as "closed" then the firewall has rejected the packet and sent back a packet with the "RST" flag. If it's sending packets, the machine is on.

and if the result comes back as "filtered" then your machine is off because it will have sent back no packets (unless your firewall is configured to "DROP" then nmap will have no way of knowing if the machine is off or if the firewall is set to "DROP")

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Yes, that was perfect. I forgot about the strcpy, I remembered the need for the null character at the end and I defined space for that in the array when I declared the variable but overlooked the fact that character strings in the format I was using is not part of the standard library. I added "#include <string.h>" to the preproccessor and used "strcpy" and everything went perfectly. Thanks!

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The only answer I have for that is that the book I am going through taught me that way. I'm going to guess it taught me that way because when dealing with input from a user, it can't be assumed the user will always input a type of data that is compatible with what is in the program. So to make up for that, I start as a char because that could be anything from the keyboard and then safely convert it into something the program can use. I could be wrong though, I'm pretty new to this.