Angel David Yaguana Hernandez / Mbed 2 deprecated CPP_fread

fread, descripcion y ejemplo

Dependencies:   mbed

main.cpp@0:2191a269e668, 2012-04-03 (annotated)

Committer:
sherckuith
Date:
Tue Apr 03 21:01:22 2012 +0000
Revision:
0:2191a269e668
descripcion y ejemplo

Who changed what in which revision?

UserRevisionLine numberNew contents of line
sherckuith 0:2191a269e668 1 #include "mbed.h"
sherckuith 0:2191a269e668 2 #include "SDFileSystem.h"
sherckuith 0:2191a269e668 3
sherckuith 0:2191a269e668 4 Serial pc(USBTX, USBRX);
sherckuith 0:2191a269e668 5 LocalFileSystem chip("uc");
sherckuith 0:2191a269e668 6 SDFileSystem sd(p5, p6, p7, p8,"sd");
sherckuith 0:2191a269e668 7
sherckuith 0:2191a269e668 8 int main () {
sherckuith 0:2191a269e668 9 pc.baud(115200);
sherckuith 0:2191a269e668 10 FILE * pFile;
sherckuith 0:2191a269e668 11 long lSize;
sherckuith 0:2191a269e668 12 char * buffer;
sherckuith 0:2191a269e668 13 size_t result;
sherckuith 0:2191a269e668 14
sherckuith 0:2191a269e668 15 pFile = fopen ( "/sd/Justin.mp3","r");
sherckuith 0:2191a269e668 16 if (pFile==NULL) {
sherckuith 0:2191a269e668 17 fputs ("File error",stderr);
sherckuith 0:2191a269e668 18 exit (1);
sherckuith 0:2191a269e668 19 }
sherckuith 0:2191a269e668 20 // obtain file size:
sherckuith 0:2191a269e668 21 fseek (pFile , 0 , SEEK_END);
sherckuith 0:2191a269e668 22 lSize = ftell (pFile);
sherckuith 0:2191a269e668 23 rewind (pFile);
sherckuith 0:2191a269e668 24 pc.printf("Tamanio: %d\n",lSize);
sherckuith 0:2191a269e668 25 wait(3);
sherckuith 0:2191a269e668 26 // allocate memory to contain the whole file:
sherckuith 0:2191a269e668 27 buffer = (char*) malloc (sizeof(char)*lSize);
sherckuith 0:2191a269e668 28 if (buffer == NULL) {
sherckuith 0:2191a269e668 29 fputs ("Memory error",stderr);
sherckuith 0:2191a269e668 30 exit (2);
sherckuith 0:2191a269e668 31 }
sherckuith 0:2191a269e668 32 // copy the file into the buffer:
sherckuith 0:2191a269e668 33 result = fread (buffer,1,lSize,pFile);
sherckuith 0:2191a269e668 34 if (result != lSize) {
sherckuith 0:2191a269e668 35 fputs ("Reading error",stderr);
sherckuith 0:2191a269e668 36 exit (3);
sherckuith 0:2191a269e668 37 }
sherckuith 0:2191a269e668 38 pc.printf("%s",buffer);
sherckuith 0:2191a269e668 39 /* the whole file is now loaded in the memory buffer. */
sherckuith 0:2191a269e668 40 fclose (pFile);
sherckuith 0:2191a269e668 41 free (buffer);
sherckuith 0:2191a269e668 42 return 0;
sherckuith 0:2191a269e668 43 }
sherckuith 0:2191a269e668 44
sherckuith 0:2191a269e668 45 //This code loads myfile.bin into a dynamically allocated memory buffer,
sherckuith 0:2191a269e668 46 //which can be used to manipulate the content of a file as an array.
sherckuith 0:2191a269e668 47
sherckuith 0:2191a269e668 48
sherckuith 0:2191a269e668 49 /*
sherckuith 0:2191a269e668 50 function: fread
sherckuith 0:2191a269e668 51 Library: <cstdio>
sherckuith 0:2191a269e668 52
sherckuith 0:2191a269e668 53 size_t fread ( void * ptr, size_t size, size_t count, FILE * stream );
sherckuith 0:2191a269e668 54
sherckuith 0:2191a269e668 55 Read block of data from stream
sherckuith 0:2191a269e668 56 Reads an array of count elements, each one with a size of size bytes, from the stream and stores them in the block of memory specified by ptr.
sherckuith 0:2191a269e668 57 The postion indicator of the stream is advanced by the total amount of bytes read.
sherckuith 0:2191a269e668 58 The total amount of bytes read if successful is (size * count).
sherckuith 0:2191a269e668 59
sherckuith 0:2191a269e668 60 Parameters
sherckuith 0:2191a269e668 61
sherckuith 0:2191a269e668 62 ptr Pointer to a block of memory with a minimum size of (size*count) bytes.
sherckuith 0:2191a269e668 63 size Size in bytes of each element to be read.
sherckuith 0:2191a269e668 64 count Number of elements, each one with a size of size bytes.
sherckuith 0:2191a269e668 65 stream Pointer to a FILE object that specifies an input stream.
sherckuith 0:2191a269e668 66
sherckuith 0:2191a269e668 67
sherckuith 0:2191a269e668 68 Return Value
sherckuith 0:2191a269e668 69 The total number of elements successfully read is returned as a size_t object, which is an integral data type.
sherckuith 0:2191a269e668 70 If this number differs from the count parameter, either an error occured or the End Of File was reached.
sherckuith 0:2191a269e668 71 You can use either ferror or feof to check whether an error happened or the End-of-File was reached.
sherckuith 0:2191a269e668 72 */
sherckuith 0:2191a269e668 73
sherckuith 0:2191a269e668 74