Checking existence of a file (#FILE EXIST)
The command #FILE EXIST checks whether a file exists in the file system and can open it. After calling #FILE EXIST the call result is saved to V.G. variables. This is retained until the next time #FILE EXIST is called.
V.G.<var_name> |
Meaning |
Data type |
Unit for | Permitted access |
FILE_EXIST | Result of data search. When the file is found, then 1 | Boolean | 0 , 1 | R |
FILE_EXIST_PATH_NAME * | Path with file name* | String | - | R |
FILE_EXIST_DIRECTORY * | Path without file name. The path ends with '\' * | String | - | R |
* Paths that are entered in the table of search paths in the start-up list (P-STUP-00018) or channel list (P-CHAN-00401) .
Syntax: |
#FILE EXIST [ PATH="<filename>" ] |
PATH= | Name of the file whose existence is to be checked with or without directory specification. |
The equals sign (=) is optional.
Notice | |
RELATIVE DIRECTORIES: If the PATH parameter is specified as relative, a search is made for the file in the folders of the start-up/channel parameter list. The search is for the sequence main program - subroutine - work directory. |
Programming Example
Checking the existence of a file