FileTools[Text]

 read a line from a file

Parameters

 file - file descriptor or filename

Description

 • The ReadLine(file) command reads a string containing all the characters from the current file position to the first newline character or the end of file.  The characters are returned as a string.
 • If the current file position is the end of the file, a call to ReadLine returns NULL, but ReadLine does not automatically close file. This behavior is different from readline.

Examples

 > $\mathrm{FileTools}\left[\mathrm{Text}\right]\left[\mathrm{WriteLine}\right]\left("testfile","This is a test"\right)$
 ${15}$ (1)
 > $\mathrm{FileTools}\left[\mathrm{Text}\right]\left[\mathrm{WriteLine}\right]\left("testfile","This is also a test"\right)$
 ${20}$ (2)
 > $\mathrm{FileTools}\left[\mathrm{Text}\right]\left[\mathrm{Close}\right]\left("testfile"\right)$
 > $\mathrm{FileTools}\left[\mathrm{Text}\right]\left[\mathrm{ReadLine}\right]\left("testfile"\right)$
 ${"This is a test"}$ (3)
 > $\mathrm{FileTools}\left[\mathrm{Text}\right]\left[\mathrm{ReadLine}\right]\left("testfile"\right)$
 ${"This is also a test"}$ (4)
 > $\mathrm{FileTools}\left[\mathrm{Text}\right]\left[\mathrm{ReadLine}\right]\left("testfile"\right)$
 > $\mathrm{FileTools}\left[\mathrm{Remove}\right]\left("testfile"\right)$