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fopen (msvcrt)
Opens a file. More-secure versions of these functions are available; see fopen_s, _wfopen_s.

C# Signature:

[DllImport("msvcrt.dll", CallingConvention=CallingConvention.Cdecl, CharSet=CharSet.Ansi, SetLastError=true)]
public static extern IntPtr fopen(String filename, String mode);
[DllImport("msvcrt.dll", CallingConvention=CallingConvention.Cdecl, CharSet=CharSet.Unicode, SetLastError=true)]
public static extern IntPtr _wfopen(String filename, String mode);

VB Signature:

<DllImport("msvcrt.dll", CallingConvention:=CallingConvention.Cdecl, CharSet:=CharSet.Ansi, SetLastError:=True)> _
Public Shared Function fopen(ByVal filename As String, ByVal mode As String) As IntPtr
End Function
<DllImport("msvcrt.dll", CallingConvention:=CallingConvention.Cdecl, CharSet:=CharSet.Unicode, SetLastError:=True)> _
Public Shared Function _wfopen(ByVal filename As String, ByVal mode As String) As IntPtr
End Function

Alternative Managed API:



Use _wfopen whenever possible; fopen doesn't support Unicode.

Tips & Tricks:

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Sample Code:

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See Also

fopen_s (includes _wfopen_s)

fopen on MSDN

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