NsisFile plug-in

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Author: Wizou (talk, contrib)


nsisFile Plugin Homepage


nsisFile is a small NSIS plugin that manipulate file content, especially binary data.

You can typically use it to:

  • search for binary patterns in file
  • read or write (patch) binary data from/to binary files


The following is taken from the readme file in the downloadable zip file:

nsisFile::BinToHex <string>
Convert a string into an hexadecimal string representing the equivalent ANSI character bytes
No terminating NUL (00) character and no formatting characters are added.
nsisFile::HexToBin <hex string>
Convert an hexadecimal string representing ANSI characters bytes into the equivalent string
The string might be truncated to the first NUL (00) character encoutered.
Eventual formatting characters are ignored.
nsisFile::FileReadBytes <file handle> <length>
Read <length> bytes from the given file and return them as an hexadecimal string
nsisFile::FileWriteBytes <file handle> <hex string>
Write to the given file the bytes sequence, given as hexadecimal string
nsisFile::FileFindBytes <file handle> <hex string> <length>
Search the given file for the bytes sequence, given as hexadecimal string.
The search is done over <length> bytes from the file (this value should include the length of the bytes sequence)
Use -1 as <length> to search the whole file.
The result is -1 if not found, or the file offset found. (File pointer is automatically positioned to this offset)
nsisFile::FileTruncate <file handle>
Truncate the given opened file at the current file pointer (as positioned by NSIS FileSeek)


  • File handle is the value returned by NSIS FileOpen function
  • Function result is returned on NSIS stack (use Pop to retrieve it)
  • You can use NSIS FileSeek function to move to a specific offset before calling these functions to specify where to start the operation


nsisFile Plugin Homepage

ZIP archive contains the plug-in DLLs (ANSI & Unicode NSIS) as well as documentation, source code and sample script

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