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Open

(Re)opens a file.

Syntax:

f := Open(name, mode);
ok := Open(f);

File
  f  
string
  name  
string
  mode  
boolean
  ok  

See also:  BagRead, BagWrite, Close, ECHOon, ECHOoff, FLDin, FLDout, LOFILES

Description:

The Open function opens the file specified in the argument name. The type of operations you intend to perform on the file must be given in the argument {\tt mode}. The following table explains the values that the mode string can take.\medskip \begin{tabular}{lp{7cm}} Access mode & Interpretation \hline "r" & Opens file for read operations. "w" & Opens a new file for writing. If the file exists, its content is destroyed. "a" & Opens file for appending. A new file is created if the file does not exist. "R" & Opens file for {\sl unbuffered} read operations. This mode should be used in connection with the FLDin function. \end{tabular}\medskip If the file is successfully opened, Open returns a File object f, an object to be used in subsequent I/O operations on the file. The File object is a structure which contains information about the name of the file, the access mode and the status indicating whether the file is opened or closed. In case of an error, {\tt Open} returns false.\bigskip


Example:

We will open, close and reopen a file named "dummy".

kash> f := Open("dummy","w");
Filename: dummy / Mode: w / Open (fid): 5
kash> Close(f);
true
kash> f;
Filename: dummy / Mode: w / Closed
kash> Open(f);
true
kash> f;
Filename: dummy / Mode: w / Open (fid): 5


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