I’m hoping someone could shed some light on how to make the parent wait for ALL child processes to finish before continuing after the fork. I have cleanup code which I want to run but the child processes need to have returned before this can happen.
0x01 is the least significant bit set, hence the decimal value is 1. 0x80 is the most significant bit of an 8-bit byte set. If it is stored in a signed char (on a machine that uses 2’s-complement notation – as most machines you are likely to come across will), it is the most negative … Read more
Flushing the output buffers: or Can be a very helpful technique. Why would you want to flush an output buffer? Usually when I do it, it’s because the code is crashing and I’m trying to debug something. The standard buffer will not print everytime you call printf() it waits until it’s full then dumps a bunch at … Read more
You need to include the appropriate header If you’re not sure which header a standard function is defined in, the function’s man page will state this.
Change the line where you print the output to: See the docs here
This happens because declaring variables inside a for loop wasn’t valid C until C99(which is the standard of C published in 1999), you can either declare your counter outside the for as pointed out by others or use the -std=c99 flag to tell the compiler explicitly that you’re using this standard and it should interpret … Read more
C does not really have multi-dimensional arrays, but there are several ways to simulate them. The way to pass such arrays to a function depends on the way used to simulate the multiple dimensions: 1) Use an array of arrays. This can only be used if your array bounds are fully determined at compile time, … Read more
You actually compile the source code of test.c twice: The first time when compiling test.c itself, The second time when compiling main.c which includes all the test.c source. What you need in your main.c in order to use the test() function is a simple declaration, not its definition. This is achieved by including a test.h … Read more
No, stdin is not “a memory address”. It’s an I/O stream, basically an operating-system level abstraction that allows data to be read (or written, in the case of stdout). You need to use the proper stream-oriented I/O functions to read from the stream. Of course you can read from RAM too, so it’s best to write your own … Read more
In C89 standard, initializer list must be compile time constants expressions, hence the warnings. However in C99 it is supported. In C89, you can do: