fopen

#include <stdio.h>

FILE* fopen  (
    const char* filename,    /* file to  open  */
    const char* mode);       /* type of access */

The function fopen opens a file for reading or writing. The parameter filename is a pointer defining the file to open. The parameter mode is a pointer defining the access type.

The function is included in the library RL-FlashFS. The prototype is defined in the file stdio.h.

filename can include a path. If the path does not exist, all subfolders are created. filename can have the following prefixes:

The parameter mode can have the following values:

note

File update modes are only supported on FAT file system!

• a file handler - on success.
• a null pointer - on error.

fclose, fflush, fseek, rewind

#include <rtl.h>
#include <stdio.h>

void tst_fopen (void)  {
  FILE *f;

  f = fopen ("Test.txt","r");                      /* Open a file from default drive. */
  if (f == NULL)  {
    printf ("File not found!\n");
  }
  else  {
    // process file content
    fclose (f);
  }

  f = fopen ("M:\\Temp_Files\\Dump_file.log","w"); /* Create a file in subfolder on SD card.*/
  if (f == NULL)  {
    printf ("Failed to create a file!\n");
  }
  else  {
    // write data to file
    fclose (f);
  }
}