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system call

A request a program makes to the operating system, such as "open this file".

A system call transfers control to the operating system kernel to perform a privileged operation (open, read, write, spawn); Rust's std wraps them in portable APIs.

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Examples

  • File::open("notes.txt") passes through std::fs and std's platform layer down to the kernel, which answers with a file descriptor or an error.

See also

file descriptor unsafe block standard library
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