# umask Convert umask from string &lt;-> number. ## Installation & Use ``` $ npm install -S umask var umask = require('umask'); console.log(umask.toString(18)); // 0022 console.log(umask.fromString('0777')) // 511 ``` ## API ### `toString( val )` Converts `val` to a 0-padded octal string. `val` is assumed to be a Number in the correct range (0..511) ### `fromString( val, [cb] )` Converts `val` to a Number that can be used as a umask. `val` can be of the following forms: * String containing octal number (leading 0) * String containing decimal number * Number In all cases above, the value obtained is then converted to an integer and checked against the legal `umask` range 0..511 `fromString` can be used as a simple converter, with no error feedback, by omitting the optional callback argument `cb`: ``` var mask = umask.fromString(val); // mask is now the umask descibed by val or // the default, 0022 (18 dec) ``` The callback arguments are `(err, val)` where `err` is either `null` or an Error object and `val` is either the converted umask or the default umask, `0022`. ``` umask.fromString(val, function (err, val) { if (err) { console.error("invalid umask: " + err.message) } /* do something with val */ }); ``` The callback, if provided, is always called **synchronously**. ### `validate( data, k, val )` This is a validation function of the form expected by `nopt`. If `val` is a valid umask, the function returns true and sets `data[k]`. If `val` is not a valid umask, the function returns false. The `validate` function is stricter than `fromString`: it only accepts Number or octal String values, and the String value must begin with `0`. The `validate` function does **not** accept Strings containing decimal numbers. # Maintainer Sam Mikes <smikes@cubane.com> # License MIT