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Read text lines from a file

Source: R/readLines.R
readLines.Rd

This is a drop in replacement for base::readLines() with restricted functionality. Compared to base::readLines() it:

  • Only works with file paths, not connections.

  • Assumes the files are always UTF-8 encoded.

  • Does not warn or skip embedded nulls, they will likely crash R.

  • Does not warn if the file is missing the end of line character.

  • The arguments ok, warn, encoding and skipNul are ignored, with a warning.

Usage

readLines(con, n = -1, ok, warn, encoding, skipNul)

Arguments

con

A character string of the path to a file. Throws an error if a connection object is passed.

n

integer. The number of lines to read. A negative number means read all the lines in the file.

ok

Ignored, with a warning.

warn

Ignored, with a warning.

encoding

Ignored, with a warning.

skipNul

Ignored, with a warning.

Value

A UTF-8 encoded character vector of the lines in the file.

See also

writeLines()

Examples

authors_file <- file.path(R.home("doc"), "AUTHORS")
data <- readLines(authors_file)

# Trying to use connections throws an error
con <- file(authors_file)
try(readLines(con))
#> Error : Only file paths are supported by brio::readLines()
close(con)

# Trying to use unsupported args throws a warning
data <- readLines(authors_file, encoding = "UTF-16")
#> Warning: `encoding` is ignored by brio::readLines()