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Transfer binary data to and from connections

Source: R/s3_conn.R
read_write.Rd

These methods mask the identical functions in the base package (see base::readBin(), base::readLines(), base::readChar(), base::writeBin(), base::writeLines() and base::writeChar(). They behave exactly the same as their base counterpart, with the exception that they can read and write to connections opened with adf_file_con().

Usage

readBin(
  con,
  what,
  n = 1L,
  size = NA_integer_,
  signed = TRUE,
  endian = .Platform$endian
)

# Default S3 method
readBin(
  con,
  what,
  n = 1L,
  size = NA_integer_,
  signed = TRUE,
  endian = .Platform$endian
)

# S3 method for class 'adf_file_con'
readBin(
  con,
  what,
  n = 1L,
  size = NA_integer_,
  signed = TRUE,
  endian = .Platform$endian
)

readLines(
  con,
  n = -1L,
  ok = TRUE,
  warn = TRUE,
  encoding = "unknown",
  skipNul = FALSE
)

# Default S3 method
readLines(
  con = stdin(),
  n = -1L,
  ok = TRUE,
  warn = TRUE,
  encoding = "unknown",
  skipNul = FALSE
)

# S3 method for class 'adf_file_con'
readLines(
  con,
  n = -1L,
  ok = TRUE,
  warn = TRUE,
  encoding = "unknown",
  skipNul = FALSE
)

writeBin(
  object,
  con,
  size = NA_integer_,
  endian = .Platform$endian,
  useBytes = FALSE
)

# Default S3 method
writeBin(
  object,
  con,
  size = NA_integer_,
  endian = .Platform$endian,
  useBytes = FALSE
)

# S3 method for class 'adf_file_con'
writeBin(
  object,
  con,
  size = NA_integer_,
  endian = .Platform$endian,
  useBytes = FALSE
)

writeLines(text, con, sep = "\n", useBytes = FALSE)

# Default S3 method
writeLines(text, con = stdout(), sep = "\n", useBytes = FALSE)

# S3 method for class 'adf_file_con'
writeLines(text, con = stdout(), sep = "\n", useBytes = FALSE)

Arguments

con

A connection to a file on a virtual ADF device. Such a connection can be established with adf_file_con().

what

Either an object whose mode will give the mode of the vector to be read, or a character vector of length one describing the mode: one of "numeric", "double", "integer", "int", "logical", "complex", "character", "raw".

n

numeric. The (maximal) number of records to be read. You can use an over-estimate here, but not too large as storage is reserved for n items.

size

integer. The number of bytes per element in the byte stream. The default, NA_integer_, uses the natural size. Size changing is not supported for raw and complex vectors.

signed

logical. Only used for integers of sizes 1 and 2, when it determines if the quantity on file should be regarded as a signed or unsigned integer.

endian

The endian-ness ("big" or "little") of the target system for the file. Using "swap" will force swapping endian-ness.

ok

logical. Is it OK to reach the end of the connection before n > 0 lines are read? If not, an error will be generated.

warn

logical. Warn if a text file is missing a final EOL or if there are embedded nuls in the file.

encoding

encoding to be assumed for input strings. It is used to mark character strings as known to be in Latin-1, UTF-8 or to be bytes: it is not used to re-encode the input. To do the latter, specify the encoding as part of the connection con or via options(encoding=): see the examples and ‘Details’.

skipNul

logical: should nuls be skipped?

object

An R object to be written to the connection.

useBytes

See writeLines.

text

A character vector

sep

character string. A string to be written to the connection after each line of text.

Value

Returns NULL invisibly