MTA:Eir/FileSystem/file/readInt

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This function attempts to read an integer (native type) from a file and return it. The amount of bytes read should be four.

Syntax

int file:readInt ()

Returns

Returns an integer if it was successfully read from the file, false otherwise.

Example

Click to collapse [-]
Client

This snippet demonstrates an encrypted Lua source code format. 

-- Have some pieces of source code as samples.
local sourceSamples = {
[[print("Hello World!");]],
[[print("Ballas on the streets.");]],
[[return 1+1==0;]]
};

local function packSourceCode( theFile, sourceString )
    -- Encrypt the source code.
    local encryptedCode = teaEncode( sourceString );

    -- Write the file header.
    theFile:writeInt( #encryptedCode );

    -- Write file contents.
    theFile:write( encryptedCode );
end

local function unpackSourceCode( theFile )
    -- Grab the source code from the file.
    local encryptedLen = theFile:readInt();

    -- Has the length been read correctly?
    if not ( encryptedLen ) then
        return false;
    end

    local encryptedSource = theFile:read( encryptedLen );

    -- Make sure it has not been fragmented.
    if not ( #encryptedSource == encryptedLen ) then
        return false;
    end

    -- Decrypt the source code.
    local sourceCode = teaDecode( encryptedSource );

    -- Return it.
    return sourceCode;
end

-- Attempt some encryption.
local theFile = fileCreate( "encryptedSource.lue" );

for m,n in ipairs( sourceSamples ) do
    packSourceCode( theFile, n );
end

-- Get the original source code again.
theFile:seek( 0, "set" );

local unencryptedSources = {};

while ( true ) do
    local code = unpackSourceCode( theFile );

    if not ( code ) then break; end

    table.insert( unencryptedSources, code );
end

FileSystem File Functions

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