apt-get update command, 114
apt-get upgrade command, 114 – 115
arch directory, 432
archives. See backups
A record (DNS), 636
ark command, 333 – 334
The Art of Unix Programming (Raymond), 159 – 160
assessing vulnerabilities, 403 – 404
assigning
permissions, 140
variable values, 259 – 260at command, 243 – 246
atomicity (ACID compliance), 521
atrm command, 245
audio. See sound
authenticated FTP servers, 578
authentication
Apache, 481 – 483
PAM, 232 – 233 , 242AuthName directive, 482
AuthType directive, 482
AuthUserFile directive, 482
autoconf command, 647 – 648
autofs command, 452
autoresponders, 602
AVI file format, 86
Avidemux, 87
awk command, 205 – 207