x86-64 syscalls

Writes rdx bytes from the buffer at rsi to the file descriptor in rdi, and returns how many it wrote. Descriptor 1 is standard output and 2 is standard error, so this is how a program prints.

Reads up to rdx bytes from the file descriptor in rdi into the buffer at rsi, and returns how many it read. Descriptor 0 is standard input, so this is how a program reads what was typed. A return of 0 means end of input.

Ends the program with the status in rdi. It never returns, and a program that reaches the end of its code without calling it runs into whatever bytes follow.

Ends every thread of the program with the status in rdi. For a program with one thread it is exit.

Opens the path at rdi with the flags in rsi and, when creating, the mode in rdx. Returns a file descriptor.

Closes the file descriptor in rdi.

Moves the read and write position of the descriptor in rdi to the offset in rsi, interpreted according to rdx, and returns the new position.

Fills the structure at rsi with what is known about the descriptor in rdi, including its size.

Moves the end of the data segment to the address in rdi, which is the oldest way to ask for more memory. Called with 0 it returns where the segment currently ends.

Maps memory: the length in rsi, the protection in rdx, the flags in r10. An anonymous private mapping is how a program asks for a block of memory it can write to.

Unmaps the mapping of rsi bytes at the address in rdi.

Sleeps for the interval at rdi, a pair of seconds and nanoseconds.

Writes the time of the clock named in rdi into the structure at rsi.

Returns the process id.

Asks a device the descriptor in rdi refers to for something outside the ordinary read and write interface, chosen by the request in rsi.