Starboard Module Reference: once.h
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Onces represent initializations that should only ever happen once per process,
in a thread-safe way.
Macros
SB_ONCE_MAX_SIZE
Max size of the SbOnceControl type.
Typedefs
SbOnceControl
An opaque handle to a once control type with reserved memory buffer of size
SB_ONCE_MAX_SIZE and aligned at void pointer type.
Definition
typedef union SbOnceControl SbOnceControl
SbOnceInitRoutine
Function pointer type for methods that can be called via the SbOnce() system.
Definition
typedef void(* SbOnceInitRoutine) (void)
Functions
SbOnce
Thread-safely runs init_routine only once.
If this once_control has not run a function yet, this function runs
init_routine in a thread-safe way and then returns true.
If SbOnce() was called with once_control before, the function returns
true immediately.
If once_control or init_routine is invalid, the function returns
false.
Declaration
bool SbOnce(SbOnceControl *once_control, SbOnceInitRoutine init_routine)
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Last updated 2025-09-03 UTC.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-09-03 UTC."],[[["\u003cp\u003e\u003ccode\u003eSbOnce\u003c/code\u003e ensures a specific initialization routine (\u003ccode\u003einit_routine\u003c/code\u003e) is executed only once per process in a thread-safe manner.\u003c/p\u003e\n"],["\u003cp\u003e\u003ccode\u003eSbOnceControl\u003c/code\u003e is an opaque handle used by \u003ccode\u003eSbOnce\u003c/code\u003e to track whether the initialization has already occurred.\u003c/p\u003e\n"],["\u003cp\u003e\u003ccode\u003eSbOnceInitRoutine\u003c/code\u003e is a function pointer type that defines the signature of the initialization function.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003eSbOnce\u003c/code\u003e function returns \u003ccode\u003etrue\u003c/code\u003e if the \u003ccode\u003einit_routine\u003c/code\u003e was executed or had already been executed, and it returns \u003ccode\u003efalse\u003c/code\u003e if the parameters provided were invalid.\u003c/p\u003e\n"]]],["The core content defines thread-safe, one-time initialization mechanisms. `SbOnceControl` is an opaque handle with a maximum size defined by `SB_ONCE_MAX_SIZE`. `SbOnceInitRoutine` is a function pointer type for initialization methods. The `SbOnce` function executes the provided `init_routine` once, ensuring thread safety. It returns `true` if the `init_routine` either ran or had already run. It returns `false` for invalid inputs.\n"],null,["Onces represent initializations that should only ever happen once per process,\nin a thread-safe way.\n\nMacros\n\nSB_ONCE_MAX_SIZE\n\nMax size of the SbOnceControl type.\n\nTypedefs\n\nSbOnceControl\n\nAn opaque handle to a once control type with reserved memory buffer of size\nSB_ONCE_MAX_SIZE and aligned at void pointer type.\n\nDefinition \n\n typedef union SbOnceControl SbOnceControl\n\nSbOnceInitRoutine\n\nFunction pointer type for methods that can be called via the SbOnce() system.\n\nDefinition \n\n typedef void(* SbOnceInitRoutine) (void)\n\nFunctions\n\nSbOnce\n\nThread-safely runs `init_routine` only once.\n\n- If this `once_control` has not run a function yet, this function runs\n `init_routine` in a thread-safe way and then returns `true`.\n\n- If SbOnce() was called with `once_control` before, the function returns\n `true` immediately.\n\n- If `once_control` or `init_routine` is invalid, the function returns\n `false`.\n\nDeclaration \n\n bool SbOnce(SbOnceControl *once_control, SbOnceInitRoutine init_routine)"]]
