Using strtol to validate integer input in ANSI C

Question

I am new to programming and to C in general and am currently studying it at university. This is for an assignment so I would like to avoid direct answers but are more after

Answer 1

OP would like to avoid direct answers ....

validate integer input

1. Separate I/O from validation - 2 different functions.

2. I/O: Assume hostile input. (Text, too much text, too little text. I/O errors.) Do you want to consume leading spaces as part of I/O? Do you want to consume leading 0 as part of I/O? (suggest not)

3. Validate the string (NULL, lead space OK?, digits after a trailing space, too short, too long, under-range, over-range, Is 123.0 an OK integer)

4. strtol() is your friend to do the heavy conversion lifting. Check how errno should be set and tested afterward. Use the endptr. Should its value be set before. How to test afterward. It consume leading spaces, is that OK? It converts text to a long, but OP wants the nebulous "integer".

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