Constants

Constants exported by the Linux module.

Module: Linux

Standard File Descriptors

Name	Type	Value	Description
Stdin	int32	0	Standard input.
Stdout	int32	1	Standard output.
Stderr	int32	2	Standard error.

These are conventional descriptor numbers. A program may close or redirect them, so the corresponding descriptor is not guaranteed to remain open.

Syscall Numbers

Name	Type	Value
SYS_READ	uint64	0
SYS_WRITE	uint64	1
SYS_CLOSE	uint64	3
SYS_MMAP	uint64	9
SYS_MUNMAP	uint64	11
SYS_BRK	uint64	12
SYS_NANOSLEEP	uint64	35
SYS_GETPID	uint64	39
SYS_EXIT	uint64	60
SYS_CLOCK_GETTIME	uint64	228

These values are valid for the Linux x86-64 syscall ABI only.

Clock IDs

Name	Type	Value	Description
CLOCK_REALTIME	int32	0	Settable wall-clock time.
CLOCK_MONOTONIC	int32	1	Monotonic time since an unspecified point.

Memory Protection

Name	Type	Value	Description
PROT_READ	int32	1	Pages may be read.
PROT_WRITE	int32	2	Pages may be written.
PROT_EXEC	int32	4	Pages may be executed.

Combine protection values with bitwise OR.

Mapping Flags

Name	Type	Value	Description
MAP_PRIVATE	int32	2	Create a private copy-on-write mapping.
MAP_ANONYMOUS	int32	32	Create a mapping not backed by a file.

let prot = PROT_READ | PROT_WRITE;
let flags = MAP_PRIVATE | MAP_ANONYMOUS;

See also

• Mmap — use memory protection and mapping flags
• ClockGetTime — use a clock ID
• Syscall0–Syscall6 — use syscall numbers directly