Hands-On System Programming with Linux

Pseudocode

The following is the wrong approach:

mygetpass(){    numtries=1    <get the password>      if (password-is-wrong) {         numtries ++         if (numtries >= 3) {            <write and log failure message>            <abort>         } } <password correct, continue>} mylogin(){    mygetpass()}

Now let's take a look at the right approach: the Unix way! Refer to the following code:

mygetpass(){   <get the password>   if (password-is-wrong)      return false;   return true;}mylogin(){    maxtries = 3    while (maxtries--) {       if (mygetpass() == true)           <move along, call other routines>    }    // If we're here, we've failed to provide the     // correct password    <write and log failure message>    <abort>}

The job of mygetpass() is to get a password from the user and check whether it's correct; it returns success or failure ...