Top "C" questions

Why is the use of alloca() not considered good practice?

alloca() allocates memory on the stack rather than on the heap, as in the case of malloc(). So, when I …

c stack malloc allocation alloca

How can I check if char* variable points to empty string?

How can I check if char* variable points to an empty string?

c pointers char

What is your favorite C programming trick?

For example, I recently came across this in the linux kernel: /* Force a compilation error if condition is true */ #define …

c

Rerouting stdin and stdout from C

I want to reopen the stdin and stdout (and perhaps stderr while I'm at it) filehandles, so that future calls …

c redirect stdio

Split string into tokens and save them in an array

How to split a string into an tokens and then save them in an array? Specifically, I have a string "…

c split strtok

Avoid trailing zeroes in printf()

I keep stumbling on the format specifiers for the printf() family of functions. What I want is to be able …

c printf

How to printf long long

I'm doing a program that aproximate PI and i'm trying to use long long, but it isn't working. Here is …

c long-integer pi

How do I align a number like this in C?

I need to align a series of numbers in C with printf() like this example: -------1 -------5 ------50 -----100 ----1000 …

c printf alignment

Differences between fork and exec

What are the differences between fork and exec?

c unix fork exec

What happens to a declared, uninitialized variable in C? Does it have a value?

If in C I write: int num; Before I assign anything to num, is the value of num indeterminate?

c initialization declaration