cat /etc/passwd | grep apache
apache:x:993:1000::/var/www:/bin/false
id -u apache
993
cat /etc/passwd | grep 993
chrony:x:995:993::/var/lib/chrony:/sbin/nologin
apache:x:993:1000::/var/www:/bin/false

$ grep -Ri 'main' /home/xieerqi/MSUD-CS2050-SPRING-2016/
/home/xieerqi/MSUD-CS2050-SPRING-2016/linkedlist.py:if __name__ == '__main__':
/home/xieerqi/MSUD-CS2050-SPRING-2016/linkedlist.py:#   unittest.main()
/home/xieerqi/MSUD-CS2050-SPRING-2016/hashtable.py:if __name__ == "__main__" :
/home/xieerqi/MSUD-CS2050-SPRING-2016/hashtable.py:   unittest.main()
/home/xieerqi/MSUD-CS2050-SPRING-2016/dijkstra_algorithm.py:if '__main__' == __name__:
/home/xieerqi/MSUD-CS2050-SPRING-2016/dijkstra_algorithm.py:    unittest.main()

Shell 86.1% Python 9.2% Awk 4.7%

if __name__ == "__main__":
    if sys.argv[1]:
        print(make_passwd(sys.argv[1]))
    else:
        print(make_passwd(6))

// the usable charset
std::string charset = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!$%&/()=?+*'#-_.:,;<>|~\\}][{ ";

unsigned char getsinglechar();
std::string makepasswd(unsigned int letters);

// randomize char
unsigned char getsinglechar()
{
    char returnvalue = rand() % 255;
    if(charset.find(returnvalue) != std::string::npos)
    {
        return returnvalue;
    }
    else
    {
        return getsinglechar();
    }
}

// password routine
std::string makepasswd(unsigned int letters)

>>> from string import printable
>>> print printable
0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ!"#$%&'()*+,-./:;<=>?@[\]^_`{|}~

import string
import [...]

...

def _is_printable(datastring):
    return set(datastring).issubset(set(string.printable))

...

>>> from string import digits, letters, punctuation
>>> printable = digits + letters + punctuation
>>> print printable
0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ!"#$%&'()*+,-./:;<=>?@[\]^_`{|}~