System Calls
- We've been using the C standard library to access OS functionality,
but that's just calling functions made of normal code.
- In order to do things, these library functions need to call into the
OS kernel.
- This is done with the syscall instruction, which works a lot like
the call instruction.
- The Linux kernel exposes about 300 syscalls.
List of Syscalls
Syscall Example
Standard file descriptors:
-
0: stdin
-
1: stdout
-
2: stderr
-
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