This is a sample to overwrite / append to existing text file.
The following text files are covered here.
[Text file to read]
- text.txt
- This is an existing string.
Overwrite text file </h 2>
The overwrite fopens with the parameter “w”.
- 【Results】
- Overwrite.
Append to text file
The append is fopen with the parameter “a”.
- 【Results】
- It is an existing string.
P.S.
memo
- If there is no file to be read in both overwrite and append, create a new one.
- The overwrite and append are only the second argument of the fopen function.
You can specify the following for fopen’s mode.
| designation | Meaning |
|---|---|
| r | Read-only (error if file does not exist) |
| w | Write only (overwrite existing contents) |
| a | Postscript only (appended to existing content) |
| r + | Read / write (error if file does not exist) |
| w + | Read / write (overwrite existing contents) |
| a + | Read / write append (appended to existing contents) |