readLines
Read or Write Multiple Lines from or to a Connection

### Description

Reads one more lines of text input from a connection.

### Usage

    readLines(con = stdin(), n = -1L, ok = TRUE, warn = TRUE,
              encoding = "unknown", skipNul = FALSE)
    writeLines(text, con = stdout(), sep = "\n", useBytes = FALSE)

### Arguments

con | a connection. By default, the standard input for readLines and standard output for writeLines.
n | an integer. The number of lines to read. The default -1L indicates readLines should read to the end of the file.
ok | a logical value. If FALSE, and readLines reaches the end of the file before n lines are read, an error is generated. If TRUE (the default), no error is produced.
warn | This argument is not yet implemented. a logical value. If flush=TRUE, this generates a warning if the final line read does not include a terminating new-line character.
encoding | This argument is not yet implemented. the string encoding to use for newly-created strings. (See Encoding.)
text | the character vector to write. Each element is written as one line.
sep | a character string. The separator between lines. The default is "\n".
useBytes | In Spotfire Enterprise Runtime for R, this argument is ignored. All strings are written using the encoding of the output connection.
skipNul | A logical value specifying how to deal with nul (0) bytes in the input file. If FALSE, then readLines warns about nul bytes, but also puts them into the output strings, thus terminating the string early. If TRUE, then the nul bytes are omitted from the output strings. If the connection encoding is one that normally includes nul bytes (such as UTF-16), this value is ignored, and these bytes are not skipped.

### Details

See readline for information about reading a character string that is one line of input.
Value

readLines | returns the lines of input (with no new-line characters) as elements of a character vector.
writeLines | returns invisible(NULL).

See Also
readline, scan, Encoding.
Examples

    tfile <- tempfile()
    writeLines(paste(Sdatasets::state.abb, Sdatasets::state.name, sep=": ")[1:10],
        con=tfile)
    readLines(tfile)
    readLines(tfile, n=3)
    conn <- file(tfile, "rt")
    readLines(conn, n=2) # first 2 lines
    readLines(conn, n=2) # next 2 lines
    close(conn)
    unlink(tfile)

Package base version 6.1.5-18
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