S

SAC (Service Access Controller), 428

SAF (Service Access Facility), 427–431

SAM (System Administration Manager), 360, 362

Samba suite, 534–535

sar command, 392–393

sar -d command, 392

sar -u command, 393

Scalar variables, in Perl, 645–649

Scheduler parameters, displaying, 433

Scheduling commands with cron, 364–365

Scheduling processes, 309–317

Scientific and engineering applications, 788

SCO (Santa Cruz Operation), 11, 24–25

SCO Group, 11

SCO lawsuit, 14

Screen-oriented mail programs, 229–238

Scribus program, 761–762

Scribus program desktop, 762

script command, 575

Scripting language

Perl as, 643

Python as, 675

Scripts. See Shell scripts

Secondary prompt, 101

Secure NFS, 447, 513–514

Secure RPC, 447, 513

Secure shell, 483

Secure signatures, PGP, 345

Security

as relative, 328

of Berkeley Remote Commands, 249–250

host-level, 250

system, 327–356

user-level, 250

Security domains level of security, 354

Security guidelines for users, 351–352

Security levels, Orange book, 353–354

Security tips for system administrators, 395–397

sed (stream editor) program, 617, 636–642

editing commands, 637

how it works, 636

removing XML tags, 638–639

replacing strings, 637

selecting lines, 637

using with awk, 638–640

select command, 606–607

Semaphores, 319

sendmail, 506–508

mail domains, 508

mail environment, 483

monitoring performance of, 507

networked mail directories, 507

security of, 490

SMTP set up, 507–508

worms in, 350

Server-side web applications, 817–827

Servers, 440–443, 445

UNIX variants on, 34

Windows NT vs. UNIX system, 32

Service denial attacks, 516

Services

configuring, 428–429

managing, 427–433

Serving web documents, explained, 457

set command, 114, 595

set command with noclobber option, 117, 120

Sets, in Python, 677

setuid programs, 395–397

setuname command, 372

s5 file system type, 404–405

sgid (set group ID) permission, 328–330

sh configuration, 109–113

sh (Bourne) shell, 93–94

Sh variables, 113–117

sh -x command, 615–616

shadow file (/etc/shadow), 334–335

share command, 448–449, 453, 512–513

shareall command, 449

Shared objects, 707

Shared resources

browsing, 453–454

displaying, 452–453

Shareware, 755–756

Shell configuration file samples, 110–113

Shell input, field separator for, 608

Shell input and output, 607–609

Shell language vs. programming languages, 585–586

Shell positional parameters, 593–595

Shell scripts, 585–616

command-line options in, 610–611

with comments, 588–589

creating, 586

debugging, 615–616

example, 586–587

exiting from, 601

explained, 93, 585

making executable, 587

running in current shell, 588

storing and running, 178, 207

Shell variables, 113–120

Shells, 5, 93–131

common, 93–94, 130

configuring, 109–113

explained, 93

interactive, 110

invoking explicitly, 587–588

running, 94–97

running scripts in current, 588

specifying, 587

table of common, 130

what it does, 95–96

shift function (Perl), 651

showmount -e command, 453–454

Shutdown, system, 373–374

shutdown command, 52, 375–376, 489

Signals, 317–320

to a process, 308

thirty most common, 318

SIGTERM (software termination signal), 308

Silicon Graphics, 26

Simple/general/extensible UNIX, 8

Single quotes ('), 127, 129

Single UNIX Specification, 16–18, 33

Single UNIX Specification Version 2, 17

Single UNIX Specification Version 3, 17–18

Single-mode editor, emacs as, 150

Single-user states, 373

Slackware, 19

Slave DNS servers, 503

sleep command, 314

SLIP (Serial Line Internet Protocol), 268

SMC (System Management Console), 359, 361

SMIT (System Management Interface Tool), 360–361

SMTP (Simple Mail Transfer Agent), 507–508

Snail mail (smail), 296

Software (add-on), 755–790

commercial, 755–756

open-source, 756–757

Software emulators, 531

Software tools, 4–7.

See also Commands

Solaris, 21–22, 39

Solaris 10, 22

Solaris file system type, 405

Solaris SMC (System Management Console), 359, 361

Solaris system administration menus, 359

sort command, 102, 562–564

sort -f command, 563

sort function (Perl), 651

sort -n command, 563

sort -r command, 563–564

sort -t command, 564

sort -u command, 564

sort uniq command, 565

Sorting file contents, 562–565

Sound and video applications (GNOME), 184–185

Sound and video applications (KDE), 215–216

Source control with CVS, 720–723

Special characters

in Perl, 672

viewing files with, 64

Special files, 62

Special permissions, 81

Special variable expansion, 590–591

Special variables for shell programs, 591–592

spell command, 573–574

split function (Perl), 664

Spoofs of the network, 516

Spooling, explained, 89

Spreadsheet applications, 765

Squid proxy server, 517–518

SRI-NIC, 500

SSH (Secure Shell), 267–268, 490

ssh command, 267–268

Stack, explained, 581

Standard error, 103–105

Standard error redirection, 104–105

Standard input, 9

Perl variables from, 648

in Python, 688–689

using paste with, 560

Standard input/output/error, in Python, 690–691

Standard I/O (input/output), 99–105

in awk, 620, 633–636

and background jobs, 106–107

in Perl, 657

in Python, 688–692

shell, 607–609

in UNIX vs. DOS, 527

Standard I/O model, 99

Standard output, 9, 574–575

Standard utilities, 7

Standards, UNIX, 14–18

StarOffice, 758

Startup, system, 373–374

Startup directories, 374

Startup (S) scripts, 374

Stateless service, NFS as, 446

Static HTML, 794

Statistically linked libraries, 707

Status directory, 463

Sticky bit, 394–395

Sticky windows, 192

stop command, 108

Stopping a command, 45

Storage blocks (file system), 404

Storage media

managing, 406–409

UNIX file system and, 401–406

Stored information, managing, 401–427

String concatenation, in Perl, 646

String methods, in Python, 681–682

String operators, in Python, 680–681

String tests, 599

Strings, 592–593

in awk, 628–629

in Java, 743

in Perl, 646–648

in Python, 679–682

replacing with sed, 637

strings command, 568–569

Structured protection level (Orange book), 354

Style sheets for HTML, 813–817

su command, 349

su-command, 370

sub keyword, in Perl, 656

Subdirectories, 57

substr function (Perl), 647–648

sudo command, 396

suexec feature of Apache, 473–474

suexec.log file (Apache), 480

suid (set user ID) permission, 328–330

suid security problems, 330

Sun Microsystems, 21–22

SunOS, 21

SunSoft, 21

Superusers, 370

administration of, 370–371

protecting, 395–396

SUSE Linux, 39

SVID (System V Interface Definition), 14–15

Swapper, explained, 307

switch statement, in Java, 736

Sybase, 768

Symbolic links (symlinks), 61, 71–72, 256

Syntactic analyzer, of gcc compiler, 708

Syntax error messages, 615

Sys module (Python), 690–691

SYS process class, 321

sysadm administrative logins, 372–373

sysdef utility, 390

System. See UNIX System

System activity reporting, 392–393

System administrator, 41, 395–397

System administrator security tips, 395–397

System call, 6, 306

System daemons

cron facility, 311

explained, 312

System definition information, displaying, 389–390

System log file handling, 415

System login names, 333

System name

displaying, 388

setting, 372

System security, 327–356

System security levels, Orange book, 353–354

System services

configuring, 428–429

managing, 427–433

System settings (KDE), 216

System software installation, 367–369

System startup directory, 463

System state 5 (firmware state), 373

System state 0 (power-down state), 373

System states

changing, 373–374

displaying, 389

table of, 375

System tools (GNOME), 185–187

System tools (KDE), 217–218

System usage, accounting for, 429–431

System V Release 5, 25

System V Verification Suite, 14