next up previous contents
Next: Other Methods Up: File Objects Previous: Methods for Writing   Contents

``Printing'' to a File

Since the write method does not append a newline character to each line which it writes to a file, it is often inconvenient to convert a program which uses the print statement (which does append newlines) to one which will direct its output to a file. To make this easier, an extended form of the print statement was introduced in version 2 of python. To use this form, it is still necessary to create a file object which is opened for writing, but instead of invoking the write method, the file object can be specified on the print statement, preceded by two right brackets (»), and followed by a comma. Thus, if we had a program which was designed to print to standard output with a statment like
         print msg;
we could modify it to write to a file called ``output.file'' by first creating a file object suitable for writing:
         try:
             outfile = open('output.file','w')
         except IOError:
             print 'output.file could not be opened'
             sys.exit(1)
and then using the following print statement:
         print >> outfile, msg;



Phil Spector 2003-11-12