1. Chapter 1 Some Basics

   1. Email Basics

   2. Requests for Comments (RFCs)

   3. Email and sendmail

   4. Basic Parts of sendmail

   5. Basic Parts of a Mail Message

   6. Basic Roles of sendmail

   7. Basic Modes of sendmail

   8. The sendmail.cf File

2. Build and Install

   1. Chapter 2 Build and Install sendmail

      1. Vendor Versus Compiling
      2. Obtain the Source
      3. The Build Script
      4. Building with m4
      5. Build sendmail
      6. Install sendmail
      7. Pitfalls
      8. Build m4 Macro Reference
      9. APPENDDEF( )
      10. confBEFORE
      11. confBLDVARIANT
      12. confBUILDBIN
      13. confCC
      14. confCCOPTS
      15. confCCOPTS_SO
      16. confCOPY
      17. confDEPEND_TYPE
      18. confDEPLIBS
      19. confDONT_INSTALL_CATMAN
      20. confEBINDIR
      21. confENVDEF and conf_prog_ENVDEF
      22. confFORCE_RMAIL
      23. confGBIN...
      24. confHFDIR
      25. confHFFILE
      26. confINCDIRS
      27. confINC...
      28. confINSTALL
      29. confINSTALL_RAWMAN
      30. confLD
      31. confLDOPTS
      32. confLDOPTS_SO
      33. confLIB...
      34. confLIBDIRS
      35. confLIBS and conf_prog_LIBS
      36. confLIBSEARCH
      37. confLIBSEARCHPATH
      38. confLN
      39. confLNOPTS
      40. confLINKS
      41. confMAN...
      42. confMAPDEF
      43. confMBIN...
      44. confMSPQOWN
      45. confMSP_QUEUE_DIR
      46. confMTCCOPTS
      47. confMTLDOPTS
      48. confNO_HELPFILE_INSTALL
      49. confNO_MAN_BUILD
      50. confNO_MAN_INSTALL
      51. confNO_STATISTICS_INSTALL
      52. confOBJADD
      53. confOPTIMIZE
      54. confRANLIB
      55. confRANLIBOPTS
      56. confREQUIRE_LIBSM
      57. confSBINDIR
      58. confSBINGRP
      59. confSBINMODE
      60. confSBINOWN
      61. confSHAREDLIB...
      62. confSHELL
      63. confSM_OS_HEADER
      64. confSMOBJADD
      65. confSMSRCADD
      66. confSONAME
      67. conf_prog_OBJADD
      68. conf_prog_SRCADD
      69. confSRCDIR
      70. confSTDIOTYPE
      71. confSTDIR
      72. confSTFILE
      73. confSTRIP
      74. confSTRIPOPTS
      75. confUBINDIR
      76. confUBINGRP
      77. confUBINMODE
      78. confUBINOWN
      79. PREPENDDEF( )

   2. Chapter 3 Tune sendmail with Compile-Time Macros

      1. Before You Begin, a Checklist
      2. To Port, Tune, or Debug
      3. Pitfalls
      4. Compile-Time Macro Reference
      5. AUTO_NIS_ALIASES
      6. BSD4_3
      7. BSD4_4
      8. DATA_PROGRESS_TIMEOUT
      9. DNSMAP
      10. DSN
      11. EGD
      12. ERRLIST_PREDEFINED
      13. FAST_PID_RECYCLE
      14. _FFR...
      15. FORK
      16. HAS...
      17. HESIOD
      18. HES_GETMAILHOST
      19. IDENTPROTO
      20. IP_SRCROUTE
      21. ...IS_BROKEN
      22. LA_TYPE
      23. LDAPMAP
      24. LOG
      25. MATCHGECOS
      26. MAX...
      27. MEMCHUNKSIZE
      28. MILTER
      29. MIME7TO8
      30. MIME8TO7
      31. NAMED_BIND
      32. MAP_NSD
      33. MAP_REGEX
      34. NDBM
      35. NEED...
      36. NET...
      37. NETINFO
      38. NEWDB
      39. NIS
      40. NISPLUS
      41. NOFTRUNCATE
      42. NO_GROUP_SET
      43. NOTUNIX
      44. _PATH...
      45. PH_MAP
      46. PICKY_HELO_CHECK
      47. PIPELINING
      48. PSBUFSIZ
      49. QUEUE
      50. QUEUESEGSIZE
      51. REQUIRES_DIR_FSYNC
      52. SASL
      53. SCANF
      54. SECUREWARE
      55. SFS_TYPE
      56. SHARE_V1
      57. SM_...
      58. SM_HEAP_CHECK
      59. SM_CONF_SHM
      60. SMTP
      61. SMTPDEBUG
      62. SMTPLINELIM
      63. SPT_TYPE
      64. STARTTLS
      65. SUID_ROOT_FILES_OK
      66. SYSLOG_BUFSIZE
      67. SYSTEM5
      68. TCPWRAPPERS
      69. TLS_NO_RSA
      70. TOBUFSIZE
      71. TTYNAME
      72. ...T
      73. UDB_DEFAULT_SPEC
      74. USE_DOUBLE_FORK
      75. USE_ENVIRON
      76. USING_NETSCAPE_LDAP
      77. USERDB
      78. USESETEUID
      79. WILDCARD_SHELL
      80. XDEBUG

   3. Chapter 4 Configure sendmail.cf with m4

      1. The m4 Preprocessor
      2. Configure with m4
      3. m4 Macros by Function
      4. Masquerading
      5. Relays
      6. UUCP Support
      7. Pitfalls
      8. Configuration File Feature Reference
      9. FEATURE(accept_unqualified_senders)
      10. FEATURE(accept_unresolvable_domains)
      11. FEATURE(access_db)
      12. FEATURE(allmasquerade)
      13. FEATURE(always_add_domain)
      14. FEATURE(authinfo)
      15. FEATURE(bestmx_is_local)
      16. FEATURE(bitdomain)
      17. FEATURE(blacklist_recipients)
      18. FEATURE(compat_check)
      19. FEATURE(delay_checks)
      20. FEATURE(dnsbl)
      21. FEATURE(domaintable)
      22. FEATURE(enhdnsbl)
      23. FEATURE(generics_entire_domain)
      24. FEATURE(genericstable)
      25. FEATURE(ldap_routing)
      26. FEATURE(limited_masquerade)
      27. FEATURE(local_lmtp)
      28. FEATURE(local_no_masquerade)
      29. FEATURE(local_procmail)
      30. FEATURE(lookupdotdomain)
      31. FEATURE(loose_relay_check)
      32. FEATURE(mailertable)
      33. FEATURE(masquerade_entire_domain)
      34. FEATURE(masquerade_envelope)
      35. FEATURE(msp)
      36. FEATURE(nocanonify)
      37. FEATURE(nodns)
      38. FEATURE(no_default_msa)
      39. FEATURE(notsticky)
      40. FEATURE(nouucp)
      41. FEATURE(nullclient)
      42. FEATURE(promiscuous_relay)
      43. FEATURE(preserve_local_plus_detail)
      44. FEATURE(preserve_luser_host)
      45. FEATURE(queuegroup)
      46. FEATURE(rbl)
      47. FEATURE(redirect)
      48. FEATURE(relay_based_on_MX)
      49. FEATURE(relay_entire_domain)
      50. FEATURE(relay_hosts_only)
      51. FEATURE(relay_local_from)
      52. FEATURE(relay_mail_from)
      53. FEATURE(smrsh)
      54. FEATURE(stickyhost)
      55. FEATURE(use_ct_file)
      56. FEATURE(use_cw_file)
      57. FEATURE(uucpdomain)
      58. FEATURE(virtuser_entire_domain)
      59. FEATURE(virtusertable)

   4. Chapter 5 Build and Use Companion Programs

      1. The Build Script
      2. -A
      3. -c
      4. -E
      5. -f
      6. -I
      7. -L
      8. -M
      9. -m
      10. -n
      11. -O
      12. -Q
      13. -S
      14. -v
      15. The editmap Program
      16. -C
      17. -f
      18. -N
      19. -q
      20. -u
      21. -x
      22. The mail.local Delivery Agent
      23. -7
      24. -b
      25. -d
      26. -D
      27. -f
      28. -h
      29. -l (lowercase L)
      30. -r
      31. The mailstats Program
      32. -c
      33. -C
      34. -f
      35. -o
      36. -p
      37. -P
      38. The makemap Program
      39. -c
      40. -C
      41. -d
      42. -e
      43. -f
      44. -l (lowercase L)
      45. -N
      46. -o
      47. -r
      48. -s
      49. -t
      50. -u
      51. -v
      52. The praliases Program
      53. -C
      54. -f
      55. The rmail Delivery Agent
      56. The smrsh Program
      57. The vacation Program
      58. -a
      59. -C
      60. -d
      61. -f
      62. -i or -I
      63. -l (lowercase L)
      64. -m
      65. -r
      66. -s
      67. -t
      68. -U
      69. -x
      70. -z
      71. Pitfalls

3. Administration

   1. Chapter 6 Tune Performance

      1. Handle Deep Queues
      2. Sidestep Slow Hosts
      3. Deliver to Files
      4. Buffered File I/O
      5. Use Multiple Queues
      6. Condition the Network
      7. Tune the Kernel
      8. Pitfalls

   2. Chapter 7 How to Handle spam

      1. The Local_check_ Rule Sets
      2. How DNSBL Works
      3. Check Headers with Rule Sets
      4. Relaying
      5. The access Database
      6. The Milter Library
      7. Pitfalls

   3. Chapter 8 Test Rule Sets with -bt

      1. Overview
      2. Configuration Lines
      3. Dump a sendmail Macro or Class
      4. Show an Item
      5. Complex Actions Made Simple
      6. Process-Specified Addresses
      7. Add Debugging for Detail
      8. Batch Rule-Set Testing
      9. Pitfalls

   4. Chapter 9 DNS and sendmail

      1. Overview
      2. How sendmail Uses DNS
      3. Set Up MX Records
      4. How to Use nslookup
      5. Prepare for Disaster
      6. Pitfalls

   5. Chapter 10 Maintain Security with sendmail

      1. Why root?
      2. The Environment
      3. SMTP Probes
      4. The Configuration File
      5. Permissions
      6. The Aliases File
      7. Forged Mail
      8. Security Features
      9. Support SMTP AUTH
      10. STARTTLS
      11. Other Security Information
      12. Pitfalls

   6. Chapter 11 Manage the Queue

      1. Overview of the Queue
      2. Parts of a Queued Message
      3. Using Multiple Queue Directories
      4. Queue Groups (V8.12 and Above)
      5. Bogus qf Files
      6. Printing the Queue
      7. How the Queue Is Processed
      8. Cause Queues to Be Processed
      9. Process Alternate Queues
      10. Pitfalls
      11. The qf File Internals
      12. A line
      13. B line
      14. C line
      15. d line
      16. D line
      17. E line
      18. F line
      19. H line
      20. I line
      21. K line
      22. M line
      23. N line
      24. P line
      25. Q line
      26. r line
      27. R line
      28. S line
      29. T line
      30. V line
      31. Z line
      32. ! line
      33. $ line
      34. . line

   7. Chapter 12 Maintain Aliases

      1. The aliases(5) File
      2. Forms of Alias Delivery
      3. Write a Delivery Agent Script
      4. Special Aliases
      5. The Aliases Database
      6. Prevent Aliasing with -n
      7. Pitfalls

   8. Chapter 13 Mailing Lists and ~/.forward

      1. Internal Mailing Lists
      2. :include: Mailing Lists
      3. Defining a Mailing List Owner
      4. Exploder Mailing Lists
      5. Problems with Mailing Lists
      6. Packages That Help
      7. The User's ~/.forward File
      8. Pitfalls

   9. Chapter 14 Signals, Transactions, and Syslog

      1. Signal the Daemon
      2. SIGTERM
      3. SIGINT
      4. SIGKILL
      5. SIGHUP
      6. SIGUSR1
      7. Log Transactions with -X
      8. Log with syslog
      9. Pitfalls
      10. Alphabetized syslog Equates
      11. arg1=
      12. bodytype=
      13. class=
      14. ctladdr=
      15. daemon=
      16. delay=
      17. dsn=
      18. from=
      19. intvl=
      20. len=
      21. mailer=
      22. msgid=
      23. nrcpts=
      24. ntries=
      25. pri=
      26. proto=
      27. reject=
      28. relay=
      29. ruleset=
      30. size=
      31. stat=
      32. to=
      33. xdelay=

   10. Chapter 15 The sendmail Command Line

       1. Alternative argv[0] Names
       2. Command-Line Switches
       3. List of Recipient Addresses
       4. Processing the Command Line
       5. sendmail's exit( ) Status
       6. EX_CANTCREAT
       7. EX_CONFIG
       8. EX_IOERR
       9. EX_OK
       10. EX_OSERR
       11. EX_OSFILE
       12. EX_SOFTWARE
       13. EX_TEMPFAIL
       14. EX_UNAVAILABLE
       15. EX_USAGE
       16. Pitfalls
       17. Alphabetized Command-Line Switches
       18. -A
       19. -B
       20. -b
       21. -ba
       22. -bD
       23. -bd
       24. -bH
       25. -bh
       26. -bi
       27. -bm
       28. -bP
       29. -bp
       30. -bs
       31. -bt
       32. -bv
       33. -bz
       34. -C
       35. -c
       36. -d
       37. -E
       38. -e
       39. -F
       40. -f
       41. -G
       42. -h
       43. -I
       44. -i
       45. -J
       46. -L
       47. -M
       48. -m
       49. -N
       50. -n
       51. -O
       52. -o
       53. -p
       54. -q
       55. -R
       56. -r
       57. -s
       58. -T
       59. -t
       60. -U
       61. -V
       62. -v
       63. -X
       64. -x

   11. Chapter 16 Debug sendmail with -d

       1. The Syntax of -d
       2. The Behavior of -d
       3. Interpret the Output
       4. Table of All -d Categories
       5. Pitfalls
       6. Reference for -d in Numerical Order
       7. -d0.1
       8. -d0.4
       9. -d0.10
       10. -d0.12
       11. -d0.13
       12. -d0.15
       13. -d0.20
       14. -d2.1
       15. -d2.9
       16. -d4.80
       17. -d6.1
       18. -d8.1
       19. -d8.2
       20. -d8.3
       21. -d8.5
       22. -d8.7
       23. -d8.8
       24. -d11.1
       25. -d11.2
       26. -d12.1
       27. -d13.1
       28. -d20.1
       29. -d21.1
       30. -d21.2
       31. -d22.1
       32. -d22.11
       33. -d22.12
       34. -d25.1
       35. -d26.1
       36. -d27.1
       37. -d27.2
       38. -d27.3
       39. -d27.4
       40. -d27.5
       41. -d27.8
       42. -d27.9
       43. -d28.1
       44. -d29.1
       45. -d29.4
       46. -d31.2
       47. -d34.1
       48. -d34.11
       49. -d35.9
       50. -d37.1
       51. -d37.8
       52. -d38.2
       53. -d38.3
       54. -d38.4
       55. -d38.9
       56. -d38.10
       57. -d38.12
       58. -d38.19
       59. -d38.20
       60. -d41.1
       61. -d44.4
       62. -d44.5
       63. -d48.2
       64. -d49.1
       65. -d52.1
       66. -d52.100
       67. -d60.1
       68. -d99.100

4. The Configuration File

   1. Chapter 17 Configuration File Overview

      1. Overall Syntax
      2. Comments
      3. V8 Comments
      4. Continuation Lines
      5. The V Configuration Command
      6. Pitfalls

   2. Chapter 18 The R (Rules) Configuration Command

      1. Why Rules?
      2. The R Configuration Command
      3. Tokenizing Rules
      4. The Workspace
      5. The Behavior of a Rule
      6. The LHS
      7. The RHS
      8. Pitfalls
      9. Rule Operator Reference
      10. $&
      11. $@
      12. $@
      13. $@
      14. $@
      15. $@
      16. $:
      17. $:
      18. $:
      19. $:
      20. $digit
      21. $=
      22. $>
      23. $[ $]
      24. $( $)
      25. $-
      26. $+
      27. $#
      28. $#
      29. $#
      30. $*
      31. $~
      32. $|

   3. Chapter 19 The S (Rule Sets) Configuration Command

      1. The S Configuration Command
      2. The Sequence of Rule Sets
      3. The canonify Rule Set 3
      4. The final Rule Set 4
      5. The parse Rule Set 0
      6. The localaddr Rule Set 5
      7. Rule Sets 1 and 2
      8. Pitfalls
      9. Policy Rule-Set Reference
      10. check_data
      11. check_etrn
      12. check_vrfy and check_expn
      13. srv_features

   4. Chapter 20 The M (Mail Delivery Agent) Configuration Command

      1. The M Configuration Command
      2. The Symbolic Delivery Agent Name
      3. The mc Configuration Syntax
      4. Delivery Agents by Name
      5. cyrus
      6. cyrusv2
      7. discard
      8. error
      9. fax
      10. *file* and *include*
      11. local and prog
      12. mail11
      13. ph
      14. pop
      15. procmail
      16. qpage
      17. smtp, etc.
      18. usenet
      19. uucp
      20. Delivery Agent Equates
      21. /= (forward slash)
      22. A=
      23. C=
      24. D=
      25. E=
      26. F=
      27. L=
      28. M=
      29. m=
      30. N=
      31. P=
      32. Q=
      33. R=
      34. r=
      35. S=
      36. T=
      37. U=
      38. W=
      39. How a Delivery Agent Is Executed
      40. Pitfalls
      41. Delivery Agent F= Flags
      42. F=%
      43. F=0 (zero)
      44. F=1 (one)
      45. F=2
      46. F=3
      47. F=5
      48. F=6
      49. F=7
      50. F=8
      51. F=9
      52. F=: (colon)
      53. F=| (vertical bar)
      54. F=/ (forward slash)
      55. F=@
      56. F=a
      57. F=A
      58. F=b
      59. F=c
      60. F=C
      61. F=d
      62. F=D
      63. F=e
      64. F=E
      65. F=f
      66. F=F
      67. F=g
      68. F=h
      69. F=i
      70. F=I (uppercase i)
      71. F=j
      72. F=k
      73. F=l (lowercase L)
      74. F=L
      75. F=m
      76. F=M
      77. F=n
      78. F=o
      79. F=p
      80. F=P
      81. F=q
      82. F=r
      83. F=R
      84. F=s
      85. F=S
      86. F=u
      87. F=U
      88. F=w
      89. F=x
      90. F=X
      91. F=z
      92. F=Z

   5. Chapter 21 The D (Define a Macro) Configuration Command

      1. Preassigned sendmail Macros
      2. Command-Line Definitions
      3. Configuration-File Definitions
      4. Macro Names
      5. Macro Expansion: $ and $&
      6. Macro Conditionals: $?, $|, and $.
      7. Macros with mc Configuration
      8. Pitfalls
      9. Alphabetized sendmail Macros
      10. $_
      11. $a
      12. ${addr_type}
      13. ${alg_bits}
      14. ${auth_authen}
      15. ${auth_author}
      16. ${auth_ssf}
      17. ${auth_type}
      18. $b
      19. ${bodytype}
      20. $B
      21. $c
      22. ${cert_issuer}
      23. ${cert_md5}
      24. ${cert_subject}
      25. ${cipher}
      26. ${cipher_bits}
      27. ${client_addr}
      28. ${client_flags}
      29. ${client_name}
      30. ${client_port}
      31. ${client_resolve}
      32. ${cn_issuer}
      33. ${cn_subject}
      34. ${currHeader}
      35. $C
      36. $d
      37. ${daemon_addr}
      38. ${daemon_family}
      39. ${daemon_flags}
      40. ${daemon_info}
      41. ${daemon_name}
      42. ${daemon_port}
      43. ${deliveryMode}
      44. ${dsn_envid}
      45. ${dsn_notify}
      46. ${dsn_ret}
      47. $D
      48. $e
      49. ${envid}
      50. $E
      51. $f
      52. $F
      53. $g
      54. $h
      55. ${hdr_name}
      56. ${hdrlen}
      57. $H
      58. $i
      59. ${if_addr}
      60. ${if_addr_out}
      61. ${if_family}
      62. ${if_family_out}
      63. ${if_name}
      64. ${if_name_out}
      65. $j
      66. $k
      67. $l (lowercase L)
      68. ${load_avg}
      69. $L
      70. $m
      71. ${mail_addr}
      72. ${mail_host}
      73. ${mail_mailer}
      74. ${msg_size}
      75. $M
      76. ${MTAHost}
      77. $n
      78. ${nrcpts}
      79. ${ntries}
      80. $o
      81. ${opMode}
      82. $p
      83. $q
      84. ${queue_interval}
      85. $r
      86. ${rcpt_addr}
      87. ${rcpt_host}
      88. ${rcpt_mailer}
      89. $R
      90. $s
      91. ${sendmailMTACluster}
      92. ${server_addr}
      93. ${server_name}
      94. $S
      95. $t
      96. ${tls_version}
      97. $u
      98. $U
      99. $v
      100. ${verify}
      101. $V
      102. $w
      103. $W
      104. $x
      105. $X
      106. $y
      107. $Y
      108. $z
      109. $Z

   6. Chapter 22 The C and F (Class Macro) Configuration Commands

      1. Class Configuration Commands
      2. Access Classes in Rules
      3. Classes with mc Configuration
      4. Internal Class Macros
      5. Pitfalls
      6. Alphabetized Class Macros
      7. $=b
      8. $={checkMIMEFieldHeaders}
      9. $={checkMIMEHeaders}
      10. $={checkMIMETextHeaders}
      11. $=e
      12. $=k
      13. $=m
      14. $=n
      15. $={persistentMacros}
      16. $=q
      17. $={ResOk}
      18. $=R
      19. $={tls}
      20. $=s
      21. $=t
      22. $=w

   7. Chapter 23 The K (Database-Map) Configuration Command

      1. Enable at Compile Time
      2. The K Configuration Command
      3. The K Command switches
      4. -A
      5. -a
      6. -D
      7. -f
      8. -k
      9. -l (lowercase L)
      10. -m
      11. -N
      12. -O
      13. -o
      14. -q
      15. -S
      16. -T
      17. -t
      18. -v
      19. -z
      20. Use $( and $) in Rules
      21. Database Maps with mc Configuration
      22. Pitfalls
      23. Alphabetized Database-Map Types
      24. arith
      25. btree
      26. bestmx
      27. dbm
      28. dequote
      29. dns
      30. hash
      31. hesiod
      32. host
      33. implicit
      34. ldap (was ldapx)
      35. macro
      36. netinfo
      37. nis
      38. nisplus
      39. nsd
      40. null
      41. ph
      42. program
      43. regex
      44. sequence
      45. stab
      46. switch
      47. syslog
      48. text
      49. userdb
      50. user

   8. Chapter 24 The O (Options) Configuration Command

      1. Overview
      2. Command-Line Options
      3. Configuration File Options
      4. Options in the mc File
      5. Alphabetical Table of All Options
      6. Option Argument Types
      7. Interrelating Options
      8. Pitfalls
      9. Alphabetized Options
      10. AliasFile
      11. AliasWait
      12. AllowBogusHELO
      13. AuthMaxBits
      14. AuthMechanisms
      15. AuthOptions
      16. AutoRebuildAliases
      17. BadRcptThrottle
      18. BlankSub
      19. CACertFile
      20. CACertPath
      21. CheckAliases
      22. CheckpointInterval
      23. ClassFactor
      24. ClientCertFile
      25. ClientKeyFile
      26. ClientPortOptions
      27. ColonOkInAddr
      28. ConnectionCacheSize
      29. ConnectionCacheTimeout
      30. ConnectionRateThrottle
      31. ConnectOnlyTo
      32. ControlSocketName
      33. DaemonPortOptions
      34. DataFileBufferSize
      35. DeadLetterDrop
      36. DefaultAuthInfo
      37. DefaultCharSet
      38. DefaultUser
      39. DelayLA
      40. DeliverByMin
      41. DeliveryMode
      42. DHParameters
      43. DialDelay
      44. DirectSubmissionModifiers
      45. DontBlameSendmail
      46. DontExpandCnames
      47. DontInitGroups
      48. DontProbeInterfaces
      49. DontPruneRoutes
      50. DoubleBounceAddress
      51. EightBitMode
      52. ErrorHeader
      53. ErrorMode
      54. FallbackMXhost
      55. FastSplit
      56. ForkEachJob
      57. ForwardPath
      58. HelpFile
      59. HoldExpensive
      60. HostsFile
      61. HostStatusDirectory
      62. IgnoreDots
      63. InputMailFilters
      64. LDAPDefaultSpec
      65. LogLevel
      66. MailboxDatabase
      67. MatchGECOS
      68. MaxAliasRecursion
      69. MaxDaemonChildren
      70. MaxHeadersLength
      71. MaxHopCount
      72. MaxMessageSize
      73. MaxMimeHeaderLength
      74. MaxQueueChildren
      75. MaxQueueRunSize
      76. MaxRecipientsPerMessage
      77. MaxRunnersPerQueue
      78. MeToo
      79. Milter
      80. MinFreeBlocks
      81. MinQueueAge
      82. MustQuoteChars
      83. NiceQueueRun
      84. NoRecipientAction
      85. OldStyleHeaders
      86. OperatorChars
      87. PidFile
      88. PostmasterCopy
      89. PrivacyOptions
      90. ProcessTitlePrefix
      91. QueueDirectory
      92. QueueFactor
      93. QueueFileMode
      94. QueueLA
      95. QueueSortOrder
      96. QueueTimeout
      97. RandFile
      98. RecipientFactor
      99. RefuseLA
      100. ResolverOptions
      101. RetryFactor
      102. RrtImpliesDsn
      103. RunAsUser
      104. SafeFileEnvironment
      105. SaveFromLine
      106. SendMimeErrors
      107. ServerCertFile
      108. ServerKeyFile
      109. ServiceSwitchFile
      110. SevenBitInput
      111. SharedMemoryKey
      112. SingleLineFromHeader
      113. SingleThreadDelivery
      114. SmtpGreetingMessage
      115. StatusFile
      116. SuperSafe
      117. TempFileMode
      118. Timeout
      119. TimeZoneSpec
      120. TLSSrvOptions
      121. TrustedUser
      122. TryNullMXList
      123. UnixFromLine
      124. UnsafeGroupWrites
      125. UseErrorsTo
      126. UseMSP
      127. UserDatabaseSpec
      128. Verbose
      129. XscriptFileBufferSize
      130. M

   9. Chapter 25 The H (Headers) Configuration Command

      1. Overview
      2. Header Names
      3. Header Field Contents
      4. ?flags? in Header Definitions
      5. Rules Check Header Contents
      6. Header Behavior in conf.c
      7. Headers and mc Configuration
      8. Headers by Category
      9. Forwarding with Resent Headers
      10. Precedence
      11. Pitfalls
      12. Alphabetized Header Reference
      13. Apparently-From:
      14. Apparently-To:
      15. Auto-Submitted:
      16. Bcc:
      17. Cc:
      18. Comments:
      19. Content-Description:
      20. Content-Disposition:
      21. Content-Id:
      22. Content-Length:
      23. Content-Transfer-Encoding:
      24. Content-Type:
      25. Date:
      26. Delivered-To:
      27. Disposition-Notification-To:
      28. Encrypted:
      29. Errors-To:
      30. From:
      31. Full-Name:
      32. In-Reply-To:
      33. Keywords:
      34. Mail-From:
      35. Message-ID:
      36. Message:
      37. MIME-Version:
      38. Posted-Date:
      39. Precedence:
      40. Priority:
      41. Received:
      42. References:
      43. Reply-To:
      44. Return-Path:
      45. Return-Receipt-To:
      46. Sender:
      47. Subject:
      48. Text:
      49. To:
      50. Via:
      51. X-Authentication-Warning:
      52. X400-Received:

5. Appendixes

   1. Appendix A The mc Configuration Macros and Directives

   2. Appendix B What's New Since V8.8

      1. Chapter 1
      2. Chapter 2
      3. Chapter 3
      4. Chapter 4
      5. Chapter 5
      6. Chapter 6
      7. Chapter 7
      8. Chapter 8
      9. Chapter 9
      10. Chapter 10
      11. Chapter 11
      12. Chapter 12
      13. Chapter 13
      14. Chapter 14
      15. Chapter 15
      16. Chapter 16
      17. Chapter 17
      18. Chapter 18
      19. Chapter 19
      20. Chapter 20
      21. Chapter 21
      22. Chapter 22
      23. Chapter 23
      24. Chapter 24
      25. Chapter 25

   3. Appendix C Error Message Reference

      1. Where Errors Are Printed
      2. Alphabetized Error Reference

   4. Appendix D The checkcompat( ) Cookbook

      1. How checkcompat( ) Works
      2. Reject Bad Body Lines
      3. Reject Excess 8-Bit Characters

   5. Appendix E A Map to Tutorial Information

      1. How to Use This Guide
      2. The Guide

6. Chapter Bibliography

   1. Requests for Comments

   2. Publications and Postings

1. Colophon

Our look is the result of reader comments, our own experimentation, and feedback from distribution channels. Distinctive covers complement our distinctive approach to technical topics, breathing personality and life into potentially dry subjects. The animal on the cover of sendmail, Third Edition is a flying fox, a species of fruit bat found chiefly on the islands of the Malay-Indonesia archipelago. Of about 4,000 species of mammals, nearly one-quarter are bats; and of these, 160 are fruit bats. Sixty of the larger fruit bats make up the flying foxes, the largest having a wingspan of five feet. While smaller insect-eating bats navigate by echolocation, fruit bats depend on a keen sense of sight and smell to perceive their environment. They roost in trees by day, sometimes in extremely large numbers called "camps." They hang from branches by one or both feet, wrap themselves in their wings, and sleep the day away. On hot days, these bats keep cool by fanning themselves with their wings.

Greatly elongated fingers form the main support for the web of skin that has allowed these mammals, alone, to master true flight. At sunset they awaken from their slumber and begin their nocturnal ramblings. A flying fox must flap its wings until it becomes horizontal to the ground before it can let go and fly away. Once airborne, they use their sensitive sense of smell to detect where flowers are blooming or fruits have ripened. Unlike most animals, fruit bats cannot generate vitamin C (a limitation shared by humans and guinea pigs); thus, it is supplied by fruit in the diet. Flying foxes can range up to 40 miles for food. Once a target is located, they are faced with a difficult landing. Sometimes they will simply crash into foliage and grab at what they can; other times they may attempt to catch a branch with their hindfeet as they fly over it and then swing upside-down; some will even attempt a difficult half-roll under a branch to grip it in the preferred position. Once attached and hanging, they will draw the flower or fruit to their mouths with a single hindfoot, or the clawed thumbs at the top of each wing. These awkward landings often cause fights among flying foxes, especially upon their return to camp at dawn. A single bad landing can cause an entire bat-laden tree to become highly agitated, full of fighting and screaming residents.

People have eaten flying foxes for ages. Samoans, who call the flying fox manu lagi (animal of the heavens) use branches bound to the end of long poles to swat the winged delicacy from the sky. Aborigines in Australia build fires beneath flying fox camps-- the smoke stupefies the prey -- and use boomerangs to knock the creatures to the ground. Darren Kelly was the production editor, George Jansen was the copyeditor, and Audrey Doyle was the proofreader for sendmail, Third Edition. Mary Brady, Linley Dolby, Matt Hutchinson, and Claire Cloutier provided quality control. Reg Aubry, Genevieve d'Entremont, and Judy Hoer provided production support. Brenda Miller updated the index from the second edition.

Edie Freedman designed the cover of this book. The cover image is a 19th-century engraving from the Dover Pictorial Archive. Emma Colby produced the cover layout with QuarkXPress 4.1 using Adobe's ITC Garamond font.

David Futato designed the interior layout. This book was converted to FrameMaker 5.5.6 with a format conversion tool created by Erik Ray, Jason McIntosh, Neil Walls, and Mike Sierra that uses Perl and XML technologies. The text font is Linotype Birka; the heading font is Adobe Myriad Condensed; and the code font is Lucas-Font's TheSans Mono Condensed. The illustrations that appear in the book were produced by Robert Romano and Jessamyn Read using Macromedia FreeHand 9 and Adobe Photoshop 6. This colophon was written by Michael Kalantarian.