328 Miscellaneous Functions

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memcpy

void memcpy(void &pToBuffer, const void &pFromBuffer, const short nNumbOfBytes)

(void) Function copies characters from pFromBuffer to pToBuffer. nBytesToCopy is the number of bytes to copy. Identical to the function found in conventional C 'string.h' library.

Parameter Explanation Data Type pToBuffer buffer to copy to void pFromBuffer buffer to copy from void nNumbOfBytes number of bytes to copy short

string sTemp = "ROBOTC"; // create a string, 'sTemp' to be "ROBOTC" char sArray[20]; // create a char array, 'sArray' of size 20 memcpy(sArray, sTemp, sizeof(sTemp)); // copy characters from 'sTemp' to 'sArray'

memset

void memset(void &pToBuffer, const short nValue, const short nNumbOfBytes)

(void) Sets a block of memory at pToBuffer to the value nValue. nNumbOfBytes is the number of bytes to set. This is a useful function for initializing the value of an array to all zeros. Identical to the function found in conventional C 'string.h' library.

Parameter Explanation Data Type pToBuffer buffer to set void nValue value to set buffer to short nNumbOfBytes number of bytes to set short

int kSendSize = 1; // we will be sending 1 byte ubyte BytesToSend[kSendSize]; // create a ubyte array of size 1 short nMsgXmit = 0; // we will be setting them to 0 memset(BytesToSend, nMsgXmit, sizeof(BytesToSend)); // set the Byte Array to 0

memcmp

intrinsic short memcmp(void &pToBuffer, void &pFromBuffer, const short nNumbOfBytes)

(void) Compares the first set bytes of the block of memory referenced by "pToBuffer" to the first number of bytes referenced by "pFromBuffer". The function will return zero if they all match or a value different from zero representing which is greater if they do not.

Parameter Explanation Data Type pToBuffer First buffer to compare. void pFromBuffer Second buffer to compare. void nNumbOfBytes Number of bytes to compare short

char temp1[5] = {'A', 'B', 'C', 'D', 'E'}; //Create an Array short result = 0; //Variable to store result result = memcmp(temp1[0], temp1[2], 2); //Perform the memory compare

memmove

void memmove(void &pToBuffer, const void &pFromBuffer, const short nNumbOfBytes)

(void) Function copies characters from pFromBuffer to pToBuffer. nBytesToCopy is the number of bytes to copy. Identical to the function found in conventional C 'string.h' library. The advantage of "memmove" is that the buffers can overlap in memory space - the "memcpy" function they cannot overlap.

Parameter Explanation Data Type pToBuffer buffer to copy to void pFromBuffer buffer to copy from void nNumbOfBytes number of bytes to copy short

task main() { string source = "ROBOTC is cool!...."; // create string variable 'source' and set it to "ROBOTC is cool!...." string destination = ""; // create string variable 'destination' and set it equal to "" int length = 15; // create int variable 'length' and set it equal to 15   memmove(destination, source, length); // copy 'length' number of bytes (15) from 'source' to 'destination'   while(true); // infinite loop to keep the debugger alive to see output // after running: // source = "ROBOTC is cool!...." // destination = "ROBOTC is cool!" }