3

I am currently running Windows 8 64-bit and I am trying to create a logging file for use with a web server. The code in question is:

func LogWebPath(requestedURL string, accessedURL string, logFile string) error {

file, _ := os.Open(logFile)
_, err = io.WriteString(file, requestedURL + ":" + accessedURL)
if(err != nil) {
  fmt.Println(err)
  return err
}
file.Close()
return errors.New("nil")
}

Whenever io.WriteString is called, the error returned is write log/visit.log: Access is denied.

I have Go installed on my system and I am using go run x.go to run my Go source.

David Thien
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2 Answers2

8

I believe you are opening the file in read only mode. Instead of os.Open you might try os.OpenFile with the appropriate flags as shown at How to append text to a file in golang? and Append to a file in Go

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Ryan E
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2

From the documentation, you have a read-only file:

Open opens the named file for reading...

You need to use os.OpenFile with the appropriate flags

Some examples

The common method for writing a file (used by ioutil.WriteFile):

f, err := os.OpenFile(filename, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, perm)

To create or append to a file:

f, err := os.OpenFile(filename, os.O_WRONLY|os.O_CREATE|os.O_APPEND, perm)

To append only to an existing file:

f, err := os.OpenFile(filename, os.O_WRONLY|os.O_APPEND, perm)
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JimB
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