file...exists

operator

Return type: Switch
 Returns:       Returns true if the named file exists and false otherwise.

Syntax
file string-expression exists


Purpose

An operator that tests whether a named file exists. Useful for avoiding overwriting a file that already exists with a new one.

For example, the following shows how a file...exists test can be used to avoid overwriting an existing file: 

  global stream error-strm
  ...
  do when file "errors.log" exists
    put #error "File errors.log already exists.%n"
    put #error "Please delete or rename it before running this program.%n"
    halt with 1
  else
    open error-strm as file "errors.log"
  done

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