How to open a file which is in read write execute mode in C (shell programming)

Question

I am trying to create a file, but it is opening in locked mode. How to make it in read write execute mode?

switch(choice){
case 1: printf("\n Enter the file: ");
    scanf("%s", file);
    open(file, O_CREAT, S_IRWXG);
    break;

Because you omit O_RDONLY, O_WRONLY and O_RDWR, you are actually opening the file in O_RDONLY mode, for all you also create it. The `S_IRWXG` flag sets `---rwx---` mode, modified by `umask`. It's most succinct to write the mode in octal: `0777` if you're sufficiently confident that you won't be attacked. Or use `S_IRWXU|S_IRWXG|S_IRWXO`. But that is still modified by `umask`. — Jonathan Leffler, Oct 20 '13 at 20:56

score 1 · Accepted Answer · answered Oct 20 '13 at 20:50

The third argument of open doesn't actually have to be one of the defined flags. If you want it in +rwe mode for all users, just change your code to

open(file, O_CREAT, 0777);

EDIT: If you'd prefer to use the flags. Just combine them with the | command. You'll end up actually passing the same value in, but many people prefer to use the flags.

How to open a file which is in read write execute mode in C (shell programming)

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