The ReadNextInteger(file) command attempts to read an integer from file. The ReadNextInteger function skips non-numeric characters until a valid integer is found.  The integer is read from file and returned.  If no characters form a valid integer, then NULL is returned.  In this case, the file is read to the end of the file.

If file is the name of a file that has not been opened, Maple attempts to open the file before attempting to read the integer.

An error is raised if file is not a valid descriptor or if it is the name of a file that cannot be opened.

$\mathrm{FileTools}\left[\mathrm{Text}\right]\left[\mathrm{WriteString}\right]\left(''testfile''\,''1\; two\; 3\; four''\right)$

$12$

$\mathrm{FileTools}\left[\mathrm{Text}\right]\left[\mathrm{Close}\right]\left(''testfile''\right)\:$

$\mathrm{FileTools}\left[\mathrm{Text}\right]\left[\mathrm{ReadNextInteger}\right]\left(''testfile''\right)$

$1$

$\mathrm{FileTools}\left[\mathrm{Text}\right]\left[\mathrm{ReadNextInteger}\right]\left(''testfile''\right)$

$3$

$\mathrm{FileTools}\left[\mathrm{Text}\right]\left[\mathrm{ReadNextInteger}\right]\left(''testfile''\right)$

$\mathrm{FileTools}\left[\mathrm{AtEndOfFile}\right]\left(''testfile''\right)$

$\mathrm{true}$