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– random module – ensure_mixedcase() function
57 lines
1.4 KiB
Markdown
57 lines
1.4 KiB
Markdown
[< back to index](../index.md)
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## stdio
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The `stdio` module automatically imports the `string` and `err` modules.
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It requires an implementation of `void putchar(byte a)` and therefore works only on targets with console output.
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#### `void putstr(pointer str, byte len)`
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Prints a string of length `len` located at address `str`.
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#### `void putstrz(pointer str)`
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Prints a null-terminated string located at address `str`.
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If the string is longer than 255 bytes, then the behaviour is undefined (might even crash).
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#### `void ensure_mixedcase()`
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On targets that have separate all-caps and mixed-case modes (like most Commodore machines), switches to the mixed-case mode.
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## err
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#### `enum error_number`
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Standard error codes. All codes other than `err_ok` suggest that the last operation failed.
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#### `error_number errno`
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The result of the last operation.
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## random
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A simple and reasonably fast random number generator. Not suitable for cryptographic or simulation uses.
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#### `word rand_seed`
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Random number generator state.
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#### `byte rand()`
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Get a random byte (0–255) and update the state of the generator.
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#### `void init_rand_seed()`
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Initializes the random number generator state.
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This may take a long time, even several frames, depending on the target.
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Current implementation:
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* On C64, spends two frames reading noise data from the SID chip.
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* On Z80, reads the refresh register.
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* On all other targets, sets the seed to 1.
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