How test if a value is (or is not) a valid pointer?
98222
Testing pointers for validity (C/C++)
13388
Check if a pointer points to allocated memory on the heap
63
How do I tell if the c function atoi failed or if it was a string of zeros?
86953
How to test whether stringstream operator>> has parsed a bad type and skip it
99415
Implementing a safe ValueQ that does not evaluate its argument
152255
Const correctness for value parameters
24250
How to know if a pointer points to the heap or the stack?
41380
How to check if a given Regex is valid?
42194
Why C standards allow you not to return a value from a function?
66487
What are the Pointer-to-Member ->* and .* Operators in C++?
73423
What is the best (idiomatic) way to check the type of a Python variable?
106634
Check if a value from scanf is a number?
30954
How do you validate a binary search tree?
28020
Error checking an inputed value
60608
Test whether string is a valid integer
3800
How do I check to see if a value is an integer in MySQL?
67473
How to determine if a string is a number with C++?