nim-binstreams is a no-dependencies Nim library that provides endianness
aware binary streams. It is a wrapper over the standard
io module, and it
for endianness conversions (included in the project), so it should be
- Support for file and memory buffer backed streams through a single interface
- Possibility to switch the endianness of a stream on the fly
- Mixed read/write streams are supported
- Generics friendly API
nim-binstreams can be installed via Nimble:
nimble install binstreams
The below example should give you a fairly good idea of the basic usage. Please refer to the API documentation for further details.
import binstreams # Create a new big-endian file stream for writing. # File modes work exactly like with `open`. var fs = newFileStream("outfile", bigEndian, fmWrite) # There's just a generic `write()` proc to write single values. # The width of the value written is determined by the type of the passed in # argument. Endianness conversions are handled automatically, if required. fs.write(3'i8) fs.write(42'i16) fs.write(0xcafe'u16) # Writing multiple values from a buffer (openArray) is just as easy. var buf = newSeq[float32](100) fs.write(buf, startIndex=5, numValues=30) # It is possible to change the endiannes of the stream at any time. fs.endian = littleEndian fs.write(12.34'f32) fs.write(0xcafebabe'i32) fs.endian = bigEndian fs.write(0xffee81'u64) # Helpers for writing strings, chars and bools are provided. fs.writeStr("some UTF-8 string") fs.writeChar('X') fs.writeBool(true) # The file position can be queried and changed at any time. let pos = fs.getPosition() fs.setPosition(0) fs.write(88'u8) fs.setPosition(pos) fs.write(12'i16) fs.close() # It is possible to create a new stream from a valid file handle. var f = open("outfile") fs = newFileStream(f, bigEndian) # The type of the value needs to be specified when doing single-value reads. echo fs.read(int8) echo fs.read(uint8) fs.endian = littleEndian echo fs.read(int16) echo fs.read(float32) # Helpers for strings, chars and bools echo fs.readStr(10) echo fs.readChar() echo fs.readBool() # Reading multiple values into a buffer fs.setPosition(5) var readBuf = newSeq[int16](30) fs.read(buf, startIndex=5, numValues=10)
Copyright © 2020 John Novak <firstname.lastname@example.org>
This work is free. You can redistribute it and/or modify it under the terms of the Do What The Fuck You Want To Public License, Version 2, as published by Sam Hocevar. See the COPYING file for more details.