fflush - Maple Help

fflush

flush output for a buffered file

 Calling Sequence fflush(file ...)

Parameters

 file - one or more names or file descriptors of open files to be flushed

Description

 • Ensures that any output which has been written to the specified file, which is assumed to have been opened either implicitly or by fopen or popen, is actually written to disk.
 • fflush does not return anything.
 • When a file is closed, it is automatically flushed.

Examples

This example will only work on Unix machines.  For other platforms, replace cat in the ssystem calling sequences with the corresponding system command.

 > $\mathrm{fd}≔\mathrm{fopen}\left(\mathrm{testFile},\mathrm{WRITE},\mathrm{TEXT}\right)$
 ${\mathrm{fd}}{≔}{0}$ (1)
 > $\mathrm{fprintf}\left(\mathrm{fd},\mathrm{This is a test }\right)$
 ${15}$ (2)
 > $\mathrm{ssystem}\left("cat testFile"\right)$
 $\left[{0}{,}{""}\right]$ (3)
 > $\mathrm{fflush}\left(\mathrm{fd}\right)$
 > $\mathrm{ssystem}\left("cat testFile"\right)$
 $\left[{0}{,}{"This is a test"}\right]$ (4)
 > $\mathrm{fclose}\left(\mathrm{fd}\right)$