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API Reference

File System API

File Writing

An example of writing a file to a LittleFS file system:

CMakeLists.txt's end should include:

target_link_libraries(fs-flash jxglib_LFS_Flash)
add_subdirectory(${CMAKE_CURRENT_LIST_DIR}/../pico-jxglib pico-jxglib)

Edit the source file as follows:

fs-flash.cpp
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#include <stdio.h>
#include "pico/stdlib.h"
#include "jxglib/LFS/Flash.h"

using namespace jxglib;

int main()
{
    ::stdio_init_all();
    LFS::Flash drive("Drive:", 0x0004'0000);  // 256kB
    if (!FS::Mount("Drive:") && !FS::Format(Stdio::Instance, "Drive:")) return 1;
    FS::File* pFile = FS::OpenFile("Drive:/test.txt", "w");
    if (pFile) {
        for (int i = 0; i < 10; ++i) {
            pFile->Printf("Line %d\n", i + 1);
        }
        pFile->Close();
        delete pFile;
    }
}
  • LFS::Flash drive("Drive", 0x0004'0000); // 256kB Creates a LittleFS file system drive named Drive with 256kB size
  • if (!FS::Mount("Drive:") && !FS::Format(Stdio::Instance, "Drive:")) return 1; Checks if the drive is mounted. If not, formats the drive
  • File* pFile = FS::OpenFile("Drive:/test.txt", "w"); Opens a file for writing
  • pFile->Printf("Line %d\n", i + 1); Writes a line to the file
  • pFile->Close(); Closes the file
  • delete pFile; Deletes the file pointer

The same operations are possible with FAT file systems.

File Reading

An example of reading a file from a LittleFS file system:

CMakeLists.txt's end should include:

target_link_libraries(fs-flash jxglib_LFS_Flash)
add_subdirectory(${CMAKE_CURRENT_LIST_DIR}/../pico-jxglib pico-jxglib)

Edit the source file as follows:

fs-flash.cpp
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#include <stdio.h>
#include "pico/stdlib.h"
#include "jxglib/LFS/Flash.h"

using namespace jxglib;

int main()
{
    ::stdio_init_all();
    LFS::Flash drive("Drive:", 0x0004'0000);  // 256kB
    FS::File* pFile = FS::OpenFile("Drive:/test.txt", "r");
    if (pFile) {
        char line[256];
        while (pFile->ReadLine(line, sizeof(line)) > 0) {
            ::printf("%s\n", line);      
        }
        pFile->Close();
        delete pFile;
    }
}
  • File* pFile = FS::OpenFile("Drive:/test.txt", "r"); Opens a file for reading
  • pFile->ReadLine(line, sizeof(line)) Reads a line from the file

Directory Information

An example of getting directory information from a LittleFS file system:

CMakeLists.txt's end should include:

target_link_libraries(fs-flash jxglib_LFS_Flash)
add_subdirectory(${CMAKE_CURRENT_LIST_DIR}/../pico-jxglib pico-jxglib)

Edit the source file as follows:

fs-flash.cpp
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#include <stdio.h>
#include "pico/stdlib.h"
#include "jxglib/LFS/Flash.h"

using namespace jxglib;

int main()
{
    ::stdio_init_all();
    LFS::Flash drive("Drive:", 0x0004'0000);  // 256kB
    FS::Dir* pDir = FS::OpenDir("Drive:/");
    if (pDir) {
        FS::FileInfo* pFileInfo;
        while (pFileInfo = pDir->Read()) {
            ::printf("%-16s%d\n", pFileInfo->GetName(), pFileInfo->GetSize());
            delete pFileInfo;
        }
        pDir->Close();
        delete pDir;
    }
}
  • FS::Dir* pDir = FS::OpenDir("Drive:/"); Opens a directory
  • pFileInfo = pDir->Read() Reads file information into an FS::FileInfo instance
  • pDir->Close(); Closes the directory

API Reference

FS::CopyFile

bool FS::CopyFile(const char* fileNameSrc, const char* fileNameDst);

Copies a file

FS::Move

bool FS::Move(const char* fileNameOld, const char* fileNameNew);

Renames or moves a file or directory (directory moving is not supported)

FS::RemoveFile

bool FS::RemoveFile(const char* fileName);

Deletes a file

FS::RemoveDir

bool FS::RemoveDir(const char* dirName);

Deletes a directory

FS::CreateDir

bool FS::CreateDir(const char* dirName);

Creates a directory

FS::ChangeCurDir

bool FS::ChangeCurDir(const char* dirName);

Changes the current directory

FS::Format

bool FS::Format(const char* driveName);

Formats the file system

FS::Mount

bool FS::Mount(const char* driveName);

Mounts the file system

FS::Unmount

bool FS::Unmount(const char* driveName);

Unmounts the file system