Crestron simpl plus language ref 사용자 설명서

Software Crestron 

®

z SIMPL+

File Functions perform file handle access from SIMPL+. Because of the overhead 
involved with maintaining current directory and file positions, there are restrictions 
on file I/O. Each SIMPL+ thread (main loop or event handler) that requires file 
operations must first identify itself with the operating system. This is done with the 
function, StartFileOperations. Before terminating the thread, the function 
EndFileOperations must be called. Files cannot be opened across threads. In other 
words, you cannot open a file in one thread (function main say) and then access the 
file with the returned file handle in another (say an event handler). This is to prevent 
two events from writing to different parts of a file. This means that you should open, 
access and then close a file within the same thread. For example, a program might be 
structured as follows:

STRING sBuf[1000];

SIGNED_INTEGER nFileHandle;

CHANGE input

{

SIGNED_INTEGER nNumRead;

StartFileOperations();

nFileHandle = FileOpen ( “\\CF0\\MyFile”, _O_RDONLY ); 

if ( nFileHandle >= 0 ) 

{

nNumRead=FileRead( nFileHandle, sBuf, 500 );          

if(nNumRead<0) 

Print (“Read Error\n”);

FileClose( nFileHandle );

}

EndFileOperations();

}

/******************************************************

Main()

Uncomment and place one-time startup code here

(This code will get called when the system starts up)

******************************************************/

Function Main()

{

SIGNED_INTEGER nNumWritten;

StartFileOperations();

nFileHandle = FileOpen ( “\\CF0\\MyFile”, _O_WRONLY );

if ( nFileHandle >= 0 ) 

{

sBuf = “Hello World!”;

nNumWritten=FileWrite( nFileHandle, sBuf, 500 );