RealView® Debugger Command Line Reference Guide 3.2.10. fread

3.2.10. fread

Reads the contents of a file into a buffer.

Syntax

unsigned long fread (buffer, count, size, fileid)
void *buffer;
unsigned count;
unsigned size;
int fileid;

where:

buffer: Specifies the start of the area into which the data is written.
count: Specifies the number of elements.
size: Specifies the size of each element in bytes.
fileid: The ID number of the file containing the data to be read. This must be a user-defined fileid.

Description

This macro reads the contents of a file into a buffer. You must define the identity of the file with either the fopen macro or the FOPEN command.

Return value

unsigned long: The size of the data that is read, and is the same as size * count. However, it returns the value -1 if an end-of-file (EOF) or error has occurred.

Rules

None

Example

This example shows how to use fread in a macro:

Create an INCLUDE file containing the following macro, for example, c:\myincludes\myfile.inc:

define /R void readFile(nElements)
  int nElements;
{
  char buffer[37];
  int nbytes;
  int recLen;
  recLen = 6;
  if (nElements > recLen)
    error(2,"Enter a number from 1 to %d.\n",recLen);
  else {
    strcpy(buffer,"One  \nTwo  \nThree\nFour \nFive \nSix  \n");
    fopen(100,"c:\\myfiles\\data.txt","w");
    nbytes = fwrite(buffer, nElements, recLen, 100);
    $printf "%d bytes written\n",nbytes$;
    fclose(100);
    fopen(100,"c:\\myfiles\\data.txt","r");
    memset(buffer,0,37);
    nbytes = fread(buffer, nElements, recLen, 100);
    $printf "%d bytes read\n",nbytes$;
    $printf "Strings:\n%s",buffer$;
    fclose(100);
  }
}
.

At the command line, include the file you created in step 1:
```
include 'c:\myincludes\myfile.inc'
```
Run the macro, specifying a value from 1 to 6:
```
readFile(4)
```

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