function::user_int16 - Linux
Overview
The user_int16
function is used to calculate the 16-bit checksum of a user-supplied buffer. This checksum can be used to verify the integrity of data during transmission or storage.
Syntax
uint16_t user_int16(void *buf, size_t buflen);
Parameters
| Parameter | Description |
|————–|————–|
| buf | Pointer to the buffer containing the data to checksum |
| buflen | Length of the buffer in bytes |
Return Value
The user_int16
function returns a 16-bit checksum of the data in the buffer. The checksum is calculated by summing the 16-bit words in the buffer and then taking the one’s complement of the sum.
Options/Flags
The user_int16
function does not support any options or flags.
Examples
The following example shows how to calculate the checksum of a buffer of data:
#include <stdio.h>
#include <stdlib.h>
int main()
{
uint8_t buf[] = { 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 0x88 };
size_t buflen = sizeof(buf);
uint16_t checksum;
checksum = user_int16(buf, buflen);
printf("Checksum: 0x%04x\n", checksum);
return 0;
}
The output of the program is:
Checksum: 0xc6d7
Common Issues
One common issue that users may encounter when using the user_int16
function is that the checksum is not correct. This can be caused by a number of factors, such as:
- The data in the buffer is corrupted.
- The buffer length is incorrect.
- The checksum algorithm is not implemented correctly.
Integration
The user_int16
function can be used with other Linux commands and tools to perform a variety of tasks. For example, it can be used to:
- Verify the integrity of data that is stored on a disk or other storage device.
- Check for errors in data that is transmitted over a network.
- Create a checksum of a file or directory for later verification.
Related Commands
The following commands are related to the user_int16
function:
user_int32
: Calculates a 32-bit checksum of a user-supplied buffer.user_crc32
: Calculates a 32-bit CRC-32 checksum of a user-supplied buffer.md5sum
: Calculates an MD5 checksum of a file or directory.sha1sum
: Calculates an SHA-1 checksum of a file or directory.