--- /dev/null
+#include <libserialport.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+/* Example of how to handle errors from libserialport.
+ *
+ * This example file is released to the public domain. */
+
+/* Pointers used in the program to resources that may need to be freed. */
+struct sp_port **port_list = NULL;
+struct sp_port_config *config = NULL;
+struct sp_port *port = NULL;
+
+/* Example of a function to clean up and exit the program with a given return code. */
+void end_program(int return_code)
+{
+ /* Free any structures we allocated. */
+ if (port_list != NULL)
+ sp_free_port_list(port_list);
+ if (config != NULL)
+ sp_free_config(config);
+ if (port != NULL)
+ sp_free_port(port);
+
+ /* Exit with the given return code. */
+ exit(return_code);
+}
+
+/* Example of a helper function for error handling. */
+int check(enum sp_return result)
+{
+ int error_code;
+ char *error_message;
+ switch (result) {
+
+ /* Handle each of the four negative error codes that can be returned.
+ *
+ * In this example, we will end the program on any error, using
+ * a different return code for each possible class of error. */
+
+ case SP_ERR_ARG:
+ /* When SP_ERR_ARG is returned, there was a problem with one
+ * or more of the arguments passed to the function, e.g. a null
+ * pointer or an invalid value. This generally implies a bug in
+ * the calling code. */
+ printf("Error: Invalid argument.\n");
+ end_program(1);
+
+ case SP_ERR_FAIL:
+ /* When SP_ERR_FAIL is returned, there was an error from the OS,
+ * which we can obtain the error code and message for. These
+ * calls must be made in the same thread as the call that
+ * returned SP_ERR_FAIL, and before any other system functions
+ * are called in that thread, or they may not return the
+ * correct results. */
+ error_code = sp_last_error_code();
+ error_message = sp_last_error_message();
+ printf("Error: Failed: OS error code: %d, message: '%s'\n",
+ error_code, error_message);
+ /* The error message should be freed after use. */
+ sp_free_error_message(error_message);
+ end_program(2);
+
+ case SP_ERR_SUPP:
+ /* When SP_ERR_SUPP is returned, the function was asked to do
+ * something that isn't supported by the current OS or device,
+ * or that libserialport doesn't know how to do in the current
+ * version. */
+ printf("Error: Not supported.\n");
+ end_program(3);
+
+ case SP_ERR_MEM:
+ /* When SP_ERR_MEM is returned, libserialport wasn't able to
+ * allocate some memory it needed. Since the library doesn't
+ * normally use any large data structures, this probably means
+ * the system is critically low on memory and recovery will
+ * require very careful handling. The library itself will
+ * always try to handle any allocation failure safely.
+ *
+ * In this example, we'll just try to exit gracefully without
+ * calling printf, which might need to allocate further memory. */
+ end_program(4);
+
+ case SP_OK:
+ default:
+ /* A return value of SP_OK, defined as zero, means that the
+ * operation succeeded. */
+ printf("Operation succeeded.\n");
+
+ /* Some fuctions can also return a value greater than zero to
+ * indicate a numeric result, such as the number of bytes read by
+ * sp_blocking_read(). So when writing an error handling wrapper
+ * function like this one, it's helpful to return the result so
+ * that it can be used. */
+ return result;
+ }
+}
+
+int main(int argc, char **argv)
+{
+ /* Call some functions that should not result in errors. */
+
+ printf("Getting list of ports.\n");
+ check(sp_list_ports(&port_list));
+
+ printf("Creating a new port configuration.\n");
+ check(sp_new_config(&config));
+
+ /* Now make a function call that will result in an error. */
+
+ printf("Trying to find a port that doesn't exist.\n");
+ check(sp_get_port_by_name("NON-EXISTENT-PORT", &port));
+
+ /* We could now clean up and exit normally if an error hadn't occured. */
+ end_program(0);
+}
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