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Fix typo in syscall-1.md

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Devon Harvey 2016-08-01 18:19:02 -04:00 committed by GitHub
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SysCall/syscall-1.md
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@ -11,7 +11,7 @@ Before we dive into Linux system call implementation, it is good to know some th
System call. What is it?
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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) kernel space function that user space programs call to handle some request.
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 other words, a system call is just a [C](https://en.wikipedia.org/wiki/C_%28programming_language%29) kernel space function that user space programs call to handle some request.
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's written in the assembly programming language: