Redirection File Defaults

If a file equation is not used to specify the characteristics of an output redirection, file the following are taken as defaults:

When output is redirected using the > filename redirection specification to a temporary file which already exists, the following defaults apply to the open:

If the >>filename specification is used instead, APPEND access is requested instead of WRITE.

A default also exists for input redirection. A file to which input has been redirected is opened by first attempting to open a temporary file with the name specified. This makes default input redirection consistent with default output redirection. If no such temporary file exists, an attempt is made to open a permanent file with that name.

When input is redirected, the file must exist and is opened with the following defaults: