I want to use mode x because as I can see from php.net that if the file exists it gives and error and also return false, and if not it creates it (also the directory's).
This is the script. It is located in www.ex.com/s/index.php
$urlParts = "/img/logo.png";
$fp = fopen( __DIR__ . $urlParts, "x" );
This should create logo.png (and also create the directory /img/) if it does not exist...but it is not working like this.
Anyone can help? Thanks!
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fopen("/img/logo.png","x");
It will not create the img directory in any case. If the directory does not exist, then it will always throw this warning.
Warning: fopen(/img/logo.png): failed to open stream: No such file or directory
fopen("logo.png","x");
If logo.png does not already exist, then it will create it without any warning. If logo.png already exists, then it will always throw this warning.
Warning: fopen(logo.png): failed to open stream: No such file or directory
fopen("","x") is equivalent to specifying O_EXCL|O_CREAT flags for the underlying open(2) system call. Now let me help you understand why it happens.
In POSIX, The O_CREAT flag causes a file to be created if it doesn't already exist. If you include the O_CREAT flag, you must also pass a third argument to open to designate the permissions. If you want to avoid writing over an existing file, use the combination O_CREAT | O_EXCL. This combination returns an error if the file already exists.
C program using POSIX
#include <fcntl.h>
#include <sys/stat.h>
int open(const char *path, int oflag, ...);
Conclusion: So we will use the "x" mode only when we want to avoid writing over an existing file.
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