Read an entire file, which may or may not be gzip compressed, directly into a ByteString.

Like readFilePS, this reads an entire file directly into a ByteString, but it is even more efficient. It involves directly mapping the file to memory. This has the advantage that the contents of the file never need to be copied. Also, under memory pressure the page may simply be discarded, wile in the case of readFilePS it would need to be written to swap. If you read many small files, mmapFilePS will be less memory-efficient than readFilePS, since each mmapFilePS takes up a separate page of memory. Also, you can run into bus errors if the file is modified.

Read standard input, which may or may not be gzip compressed, directly into a ByteString.

Pointer to a filesystem, possibly with start/end offsets. Supposed to be fed to (uncurry mmapFileByteString) or similar.

Read in a FileSegment into a Lazy ByteString. Implemented using mmap.

Decompress the given bytestring into a lazy list of chunks, along with a boolean flag indicating (if True) that the CRC was corrupted. Inspecting the flag will cause the entire list of chunks to be evaluated (but if you throw away the list immediately this should run in constant space).

Drop leading white space, where white space is defined as consisting of ' ', 't', 'n', or 'r'.

Split the input into lines, that is, sections separated by 'n' bytes, unless it is empty, in which case the result has one empty line.

Concatenate the inputs with 'n' bytes in interspersed.

Return the B.ByteString between the two lines given, or Nothing if either of them does not appear.

Precondition: the first two arguments (start and end line) must be non-empty and contain no newline bytes.

O(n) The intercalate function takes a ByteString and a list of ByteStrings and concatenates the list after interspersing the first argument between each element of the list.

Test if a ByteString is made of ascii characters

Decode a ByteString to a String according to the current locale, using lone surrogates for un-decodable bytes.

Encode a String to a ByteString according to the current locale, converting lone surrogates back to the original byte. If that fails (because the locale does not support the full unicode range) then encode using utf-8, assuming that the un-ecodable characters come from patch meta data.

See also setEnvCautiously.

Decode a ByteString containing UTF-8 to a String. Decoding errors are flagged with the U+FFFD character.

Encode a String to a ByteString using UTF-8.

Simpler but less efficient variant of betweenLinesPS. Note that this is only equivalent under the stated preconditions.