From f77fcd50233b522b34715b75ad90f4cea7b00ded Mon Sep 17 00:00:00 2001 From: Yuval Greenfield Date: Sun, 23 Aug 2015 18:08:32 -0700 Subject: [PATCH] Typo "an" to "a" --- SysCall/syscall-1.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/SysCall/syscall-1.md b/SysCall/syscall-1.md index 0965ef2..349c686 100644 --- a/SysCall/syscall-1.md +++ b/SysCall/syscall-1.md @@ -11,7 +11,7 @@ Before we will start to dive into the implementation of the system calls related System call. What is it? -------------------------------------------------------------------------------- -A system call is just an userspace request of a kernel service. Yes, the operating system kernel provides many services. When your program wants to write to or read from a file, start to listen for connections on a [socket](https://en.wikipedia.org/wiki/Network_socket), delete or create directory, or even to finish its work, a program uses a system call. In another words, a system call is just a [C](https://en.wikipedia.org/wiki/C_%28programming_language%29) function that is placed in the kernel space and an user program can ask kernel to do something via this function. +A system call is just a userspace request of a kernel service. Yes, the operating system kernel provides many services. When your program wants to write to or read from a file, start to listen for connections on a [socket](https://en.wikipedia.org/wiki/Network_socket), delete or create directory, or even to finish its work, a program uses a system call. In another words, a system call is just a [C](https://en.wikipedia.org/wiki/C_%28programming_language%29) function that is placed in the kernel space and an user program can ask kernel to do something via this function. The Linux kernel provides a set of these functions and each architecture provides its own set. For example: the [x86_64](https://en.wikipedia.org/wiki/X86-64) provides [322](https://github.com/torvalds/linux/blob/master/arch/x86/entry/syscalls/syscall_64.tbl) system calls and the [x86](https://en.wikipedia.org/wiki/X86) provides [358](https://github.com/torvalds/linux/blob/master/arch/x86/entry/syscalls/syscall_32.tbl) different system calls. Ok, a system call is just a function. Let's look on a simple `Hello world` example that written in assembly programming language: