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+# legato-util
+
+Small collection of helper functions required by some of our open source code
+
+## API
+
+### File I/O
+
+Functions to handle boilerplate when reading and writing from files.
+
+```C
+le_result_t readFromFile (const char *path, void *value,
+  int (*scanCallback) (FILE *f, void *val));
+int scanIntCallback (FILE *f, void *value);
+int scanDoubleCallback (FILE *f, void *value);
+le_result_t ioutil_readIntFromFile (const char *path, int *value);
+le_result_t ioutil_readDoubleFromFile (const char *filePath, double *value);
+le_result_t ioutil_writeToFile (const char *path, void *value, size_t size, size_t count);
+
+```
+
+### GPIO
+
+Functions to manipulate sysfs GPIO.
+
+```C
+void getGpioPath (char *outputStr, int pin, char *subDir);
+le_result_t gpio_exportPin (int pin);
+le_result_t gpio_unexportPin (int pin);
+le_result_t gpio_setDirection (int pin, char *direction);
+le_result_t gpio_setInput (int pin);
+le_result_t gpio_setOutput (int pin);
+le_result_t gpio_setActiveState (int pin, bool isActiveLow);
+le_result_t gpio_isActive (int pin, bool *isActive);
+le_result_t gpio_setValue (int pin, bool state);
+le_result_t gpio_setLow (int pin);
+le_result_t gpio_setHigh (int pin);
+
+```
+
+### Timing
+
+Functions to help with sample timing. Could potentially be replaced with system calls
+
+```C
+// TODO give these a quasi "namespace"
+void delayMicro (unsigned long microsecs);
+void delayMilli (unsigned long millisecs);
+long getTimeMicrosecs ();
+```