HTTP/2 Link IoT HAL
This topic describes the HTTP/2-related Hardware Abstraction Layer (HAL) interfaces.
HAL_Fopen
API Prototype
void *HAL_Fopen(const char *path, const char *mode)Description
Opens a file at the specified path in the specified mode. Returns a file stream.
Parameters
Parameter
Data type
Direction
Description
path
char *
Input
The file path.
mode
const char *
Input
The mode for opening the file. This parameter is compatible with the mode parameter of the standard C fopen function.
Return value
Value
Description
NULL
The operation failed.
Not NULL
Success. A file stream is returned.
HAL_Fread
API Signature
uint32_t HAL_Fread(void * buff,uint32_t size, uint32_t count, void *stream)Description
Reads data from a file stream. It reads up to `count` items of `size` bytes each.
Parameters
Parameter
Data type
Direction
Description
buff
void *
Input
Receive cache
size
uint32_t
Input
The size of each data block in bytes.
count
uint32_t
Input
The number of data blocks.
stream
void *
Input
The file stream.
Return value
Value
Description
== count
Success.
!= count
The operation failed.
HAL_Fwrite
API prototype
uint32_t HAL_Fwrite(const void * ptr, uint32_t size, uint32_t count, void * stream)Description
Writes data to a file stream. It writes up to `count` items of `size` bytes each.
Parameters
Parameter
Data type
Direction
Description
ptr
const void *
Input
A pointer to the data to write.
size
uint32_t
Input
The size of each data block in bytes.
count
uint32_t
Input
The number of data blocks.
stream
void *
Input
The file stream.
Return value
Value
Description
== count
Success.
!= count
The operation failed.
HAL_Fseek
Function prototype
int HAL_Fseek(void *stream,long offset,int framewhere)Description
Sets the file position indicator for the stream.
Parameters
Parameter
Data type
Direction
Description
stream
void *
Input
The file stream.
offset
long
Input
The position at the specified byte offset from the pointer.
framewhere
int
Input
The starting position for the offset.
0: File header
1: Current location
2: The end of the file.
Return value
Value
Description
0
Success.
-1
The operation failed.
HAL_Ftell
Interface Prototype
long HAL_Ftell(void *stream)Description
Retrieves the current value of the file position indicator for the stream. This value is the number of bytes from the beginning of the file.
Metric description
Parameter
Data type
Direction
Description
stream
void *
Input
The file stream.
Return value
Value
Description
>=0
Success. The current offset is returned.
-1
The operation failed.
HAL_Fclose
Function prototype
int HAL_Fclose(void *stream)Description
Closes the specified file stream.
Parameters
Parameter
Data type
Direction
Description
stream
void *
Input
The file stream.
Return value
Value
Description
0
Success.
-1
The operation failed.