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##

# 1.2.7.4.21 SYS_FS_FileTruncate Function

## C

    SYS_FS_RESULT SYS_FS_FileTruncate
    (
        SYS_FS_HANDLE handle
    );

## Summary

Truncates a file

## Description

This function truncates the file size to the current file read/write pointer. This function has no effect if the file read/write pointer is already pointing to end of the file.

## Precondition

A valid file handle has to be passed as input to the function. The file has to be opened in a mode where writes to file is possible (such as read plus or write mode).

## Parameters

Param | Description
--- | ---
handle | A valid handle which was obtained while opening the file.

## Returns

SYS_FS_RES_SUCCESS - File truncate operation was successful.

SYS_FS_RES_FAILURE - File truncate operation was unsuccessful. The reason for the failure can be retrieved with SYS_FS_Error or SYS_FS_FileError.

## Example

    SYS_FS_HANDLE fileHandle;
    size_t nbytes;
    size_t bytes_read;
    SYS_FS_RESULT res;

    fileHandle = SYS_FS_FileOpen("/mnt/myDrive/FILE.JPG", (SYS_FS_FILE_OPEN_READ));

    if(fileHandle != SYS_FS_HANDLE_INVALID)
    {
        // File open is successful
    }

    // Read the file content
    nbytes = sizeof(buf);
    bytes_read = SYS_FS_FileRead(fileHandle, buf, nbytes);

    // Truncate the file
    res = SYS_FS_FileTruncate(fileHandle);

    if(res != SYS_FS_RES_SUCCESS)
    {
        // Truncation failed.
    }

    SYS_FS_FileClose(fileHandle);

## Remarks

None.