The name of the subdirectory to check for the existence of.
The directory name does not support wildcard characters.
On Unix-like systems, if the first character is a ~ (tilde)
character optionally followed by a username, it is replaced by the
current or specified user's home directory.
Returns:
0
The subdirectory does not exist.
1
The subdirectory exists.
Example 8.27. RexxUtil — SysIsFileDirectory
ifSysIsFileDirectory(InputFile)thensay"Subdirectory Exists!"elsesay"Subdirectory does not exist."