packages (RPM), installing, 196–197 page numbers, printing, 140–141 partitioning hard drives (DOS), 213 passwd program, 16, 28–29 passwords changing, 16, 28–29 forgotten, 29 Linux, 212–213 for logging in, 14–17 recommendations for creating, 16–17 ssh and, 230 telnet , 230 writing on a sticky note, 348 pathnames, 93–94, 96, 122 pax command, 319–320 PCL printer language, 139 PCs. See computers percent sign (%) shell prompt, 24, 25 period (.) as grep command wildcard, 126 hiding files with, 83 not ending commands with, 31 for parent directory (..), 98–99 for working directory, 98 Perl programming language, 299 Permission denied message, 338–339 permissions, 85–89, 338–339 personal information on UNIX, 220 PHP programming language, 298–299 pico text editor, 164–168 PID (process ID), 201, 203, 204 Pine e-mail program, 249–253 pipe symbol (|), 104, 105 pipes, 80, 105–109, 333 pkg_add program, 197 plain TeX text formatter, 151 policy independence of X Windows, 43, 45 POP (Post Office Protocol), 254 pop-up windows on the Web, 278 Postnuke, 299 PostScript printers, 139, 145 pound sign (#) for comments, 116 pr command, 140–142 printers internal buffer, 140 listing, 135–137 piping output to, 109 PostScript, 139, 145 printing to specific printer, 85, 135 redirecting output to, 104 printing adding titles and page numbers, 140–141 batch formatting for, 142–145 in BSD, 134 canceling, 137–140 daemons and, 133 double-space, 142 file copy versus original, 136 files side by side, 142 finding your printout, 134–135 in Linux, 134 listing printers, 135–137 manual pages, 353–354 multiple columns, 142 non-text files, 137 overview, 84–85 PostScript and, 139, 145–146 setting margins, 141 to specific printer, 85, 135 in System V, 134 processes. See also job control continuing in the foreground, 207, 208 daemons as, 200 defined, 200 displaying with ps command, 201 killing, 209, 327–329 Lamarckian Heritability and, 205 No more processes message, 337–338 No process can be found message, 336 No such process message, 337 overview, 200 PID (process ID), 201, 203, 204 programs versus, 201 running in the background, 206 sticking in the background, 207, 208 stopping, 326–327 X Window system, 329–330 procmail mail-processing program, 260 .profile file, 115–116, 117, 189 programs. See also installing programs; specific programs commands versus, 27 directory for, 186 e-mail, 246 exiting, 57 processes versus, 201 redirecting output from full-screen, 104 redirecting output to, 104 sources for, 185–186 starting, 51–52 ps command, 201–205, 326, 328 public domain software, 35 punctuation characters. See special characters; specific characters put command (FTP), 286–287 pwd command, 95