Privilege Bracketing in the Superuser Model

The following example demonstrates how privileged operations are bracketed in the superuser model.

Example 2–1 Superuser Privilege Bracketing Example

/* Program start */
uid = getuid();
seteuid(uid);

/* Privilege bracketing */
seteuid(0);
/* Code requiring superuser capability */
...
/* End of code requiring superuser capability */
seteuid(uid);
...
/* Give up superuser ability permanently */
setreuid(uid,uid);