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User avatar
By Djames Suhanko
#80866 Hello, everyone!
The last two days I'm trying write binary data to SPIFFS, but I face a few questions and problems.
1 - is there no "wb" mode to write binary files to SPIFFS?
2 - Why using POSIX style causes exception to?

I tried this snipest code below:
Code: Select allFILE *ptr;
      byte bb[1];
      bb[0] = 0xD8;
      ptr = fopen("/teste.bin", "wb");
      fwrite(bb, 1, 1, ptr);

And with SPIFFS method, I could write file, but the mode FILE_WRITE doesn't writes them as binary data.
Some tip, please?
User avatar
By Pablo2048
#80881 Read this ... ystem.html first. Then - because the file object is a stream class IMO you can use ordinary f.write(buffPtr, size) ... (GOOGLE, Google, google next time... You probably get the answer faster than spent two days doing silly things...)
User avatar
By quackmore
#80899 from SPIFFS wiki:

Code: Select allSpiffs' API is posix-like, but not fully posix compliant.

from spiffs.h

Code: Select all/**
/* Any write to the filehandle is appended to end of the file */
#define SPIFFS_APPEND                   (1<<0)
#define SPIFFS_O_APPEND                 SPIFFS_APPEND
/* If the opened file exists, it will be truncated to zero length before opened */
#define SPIFFS_TRUNC                    (1<<1)
#define SPIFFS_O_TRUNC                  SPIFFS_TRUNC
/* If the opened file does not exist, it will be created before opened */
#define SPIFFS_CREAT                    (1<<2)
#define SPIFFS_O_CREAT                  SPIFFS_CREAT
/* The opened file may only be read */
#define SPIFFS_RDONLY                   (1<<3)
#define SPIFFS_O_RDONLY                 SPIFFS_RDONLY
/* The opened file may only be written */
#define SPIFFS_WRONLY                   (1<<4)
#define SPIFFS_O_WRONLY                 SPIFFS_WRONLY
/* The opened file may be both read and written */
#define SPIFFS_RDWR                     (SPIFFS_RDONLY | SPIFFS_WRONLY)
#define SPIFFS_O_RDWR                   SPIFFS_RDWR
/* Any writes to the filehandle will never be cached but flushed directly */
#define SPIFFS_DIRECT                   (1<<5)
#define SPIFFS_O_DIRECT                 SPIFFS_DIRECT
/* If SPIFFS_O_CREAT and SPIFFS_O_EXCL are set, SPIFFS_open() shall fail if the file exists */
#define SPIFFS_EXCL                     (1<<6)
#define SPIFFS_O_EXCL                   SPIFFS_EXCL
 * Opens/creates a file.
 * @param fs            the file system struct
 * @param path          the path of the new file
 * @param flags         the flags for the open command, can be combinations of
 * @param mode          ignored, for posix compliance
spiffs_file SPIFFS_open(spiffs *fs, const char *path, spiffs_flags flags, spiffs_mode mode);

 * Writes to given filehandle.
 * @param fs            the file system struct
 * @param fh            the filehandle
 * @param buf           the data to write
 * @param len           how much to write
 * @returns number of bytes written, or -1 if error
s32_t SPIFFS_write(spiffs *fs, spiffs_file fh, void *buf, s32_t len);

so don't think "wb" is supported but you may want to double check with SPIFFS author

anyway I'm probably missing something in your question ...
SPIFFS_write will just copy memory without caring if it it's text or not