improve homebrew cellar config example

[mandoc.git] / mandoc.1

diff --git a/mandoc.1 b/mandoc.1
index 5387ec83b303e043ab856f21618ed4e3d8a95945..173518561800b231dc5672d8d2f50df74eca454b 100644 (file)
--- a/mandoc.1
+++ b/mandoc.1
@@ -1,7 +1,7 @@
-.\"    $Id: mandoc.1,v 1.127 2014/11/30 05:29:00 schwarze Exp $
+.\"    $Id: mandoc.1,v 1.134 2015/01/20 22:45:07 schwarze Exp $

 .\"
 .\" Copyright (c) 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
 .\"
 .\" Copyright (c) 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>

-.\" Copyright (c) 2012, 2014 Ingo Schwarze <schwarze@openbsd.org>
+.\" Copyright (c) 2012, 2014, 2015 Ingo Schwarze <schwarze@openbsd.org>

 .\"
 .\" Permission to use, copy, modify, and distribute this software for any
 .\" purpose with or without fee is hereby granted, provided that the above
 .\"
 .\" Permission to use, copy, modify, and distribute this software for any
 .\" purpose with or without fee is hereby granted, provided that the above


@@ -15,7 +15,7 @@
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"

-.Dd $Mdocdate: November 30 2014 $
+.Dd $Mdocdate: January 20 2015 $

 .Dt MANDOC 1
 .Os
 .Sh NAME
 .Dt MANDOC 1
 .Os
 .Sh NAME


@@ -49,7 +49,7 @@ or
 text from stdin, implying
 .Fl m Ns Cm andoc ,
 and produces
 text from stdin, implying
 .Fl m Ns Cm andoc ,
 and produces

-.Fl T Ns Cm ascii
+.Fl T Ns Cm locale

 output.
 .Pp
 The options are as follows:
 output.
 .Pp
 The options are as follows:


@@ -85,6 +85,9 @@ Override the default operating system
 for the
 .Xr mdoc 7
 .Sq \&Os
 for the
 .Xr mdoc 7
 .Sq \&Os

+and for the
+.Xr man 7
+.Sq \&TH

 macro.
 .It Fl h
 Display only the SYNOPSIS lines.
 macro.
 .It Fl h
 Display only the SYNOPSIS lines.


@@ -146,7 +149,7 @@ See
 .Sx Output Formats
 for available formats.
 Defaults to
 .Sx Output Formats
 for available formats.
 Defaults to

-.Fl T Ns Cm ascii .
+.Fl T Ns Cm locale .

 .It Fl V
 Print version and exit.
 .It Fl W Ns Ar level
 .It Fl V
 Print version and exit.
 .It Fl W Ns Ar level


@@ -159,12 +162,13 @@ can be
 .Cm warning ,
 .Cm error ,
 or
 .Cm warning ,
 .Cm error ,
 or

-.Cm fatal .
-The default is
-.Fl W Ns Cm fatal ;
-.Fl W Ns Cm all
+.Cm unsupp ;
+.Cm all

 is an alias for
 is an alias for

-.Fl W Ns Cm warning .
+.Cm warning .
+By default,
+.Nm
+is silent.

 See
 .Sx EXIT STATUS
 and
 See
 .Sx EXIT STATUS
 and


@@ -255,7 +259,6 @@ arguments, which correspond to output modes:
 .Bl -tag -width "-Tlocale"
 .It Fl T Ns Cm ascii
 Produce 7-bit ASCII output.
 .Bl -tag -width "-Tlocale"
 .It Fl T Ns Cm ascii
 Produce 7-bit ASCII output.

-This is the default.

 See
 .Sx ASCII Output .
 .It Fl T Ns Cm html
 See
 .Sx ASCII Output .
 .It Fl T Ns Cm html


@@ -268,6 +271,7 @@ Implies
 .Fl W Ns Cm warning .
 .It Fl T Ns Cm locale
 Encode output using the current locale.
 .Fl W Ns Cm warning .
 .It Fl T Ns Cm locale
 Encode output using the current locale.

+This is the default.

 See
 .Sx Locale Output .
 .It Fl T Ns Cm man
 See
 .Sx Locale Output .
 .It Fl T Ns Cm man


@@ -299,8 +303,8 @@ If multiple input files are specified, these will be processed by the
 corresponding filter in-order.
 .Ss ASCII Output
 Output produced by
 corresponding filter in-order.
 .Ss ASCII Output
 Output produced by

-.Fl T Ns Cm ascii ,
-which is the default, is rendered in standard 7-bit ASCII documented in
+.Fl T Ns Cm ascii
+is rendered in standard 7-bit ASCII documented in

 .Xr ascii 7 .
 .Pp
 Font styles are applied by using back-spaced encoding such that an
 .Xr ascii 7 .
 .Pp
 Font styles are applied by using back-spaced encoding such that an


@@ -413,6 +417,8 @@ relative URI.
 .Ss Locale Output
 Locale-depending output encoding is triggered with
 .Fl T Ns Cm locale .
 .Ss Locale Output
 Locale-depending output encoding is triggered with
 .Fl T Ns Cm locale .

+This is the default.
+.Pp

 This option is not available on all systems: systems without locale
 support, or those whose internal representation is not natively UCS-4,
 will fall back to
 This option is not available on all systems: systems without locale
 support, or those whose internal representation is not natively UCS-4,
 will fall back to


@@ -527,19 +533,25 @@ At least one warning occurred, but no error, and
 .Fl W Ns Cm warning
 was specified.
 .It 3
 .Fl W Ns Cm warning
 was specified.
 .It 3

-At least one parsing error occurred, but no fatal error, and
+At least one parsing error occurred,
+but no unsupported feature was encountered, and

 .Fl W Ns Cm error
 or
 .Fl W Ns Cm warning
 was specified.
 .It 4
 .Fl W Ns Cm error
 or
 .Fl W Ns Cm warning
 was specified.
 .It 4

-A fatal parsing error occurred.
+At least one unsupported feature was encountered, and
+.Fl W Ns Cm unsupp ,
+.Fl W Ns Cm error
+or
+.Fl W Ns Cm warning
+was specified.

 .It 5
 Invalid command line arguments were specified.
 No input files have been read.
 .It 6
 .It 5
 Invalid command line arguments were specified.
 No input files have been read.
 .It 6

-An operating system error occurred, for example memory exhaustion or an
-error accessing input files.
+An operating system error occurred, for example exhaustion
+of memory, file descriptors, or process table entries.

 Such errors cause
 .Nm
 to exit at once, possibly in the middle of parsing or formatting a file.
 Such errors cause
 .Nm
 to exit at once, possibly in the middle of parsing or formatting a file.


@@ -598,22 +610,34 @@ fields.
 .Pp
 Message levels have the following meanings:
 .Bl -tag -width "warning"
 .Pp
 Message levels have the following meanings:
 .Bl -tag -width "warning"

-.It Cm syserr
-Opening or reading an input file failed, so the parser cannot
-even be started and no output is produced from that input file.
-.It Cm fatal
-The parser is unable to parse a given input file at all.
-No formatted output is produced from that input file.
-.It Cm error
-An input file contains syntax that cannot be safely interpreted,
-either because it is invalid or because
+.It Cm unsupp
+An input file uses unsupported low-level
+.Xr roff 7
+features.
+The output may be incomplete and/or misformatted,
+so using GNU troff instead of

 .Nm
 .Nm

-does not implement it yet.
+to process the file may be preferable.
+.It Cm error
+An input file contains invalid syntax that cannot be safely interpreted.

 By discarding part of the input or inserting missing tokens,
 the parser is able to continue, and the error does not prevent
 generation of formatted output, but typically, preparing that
 output involves information loss, broken document structure
 By discarding part of the input or inserting missing tokens,
 the parser is able to continue, and the error does not prevent
 generation of formatted output, but typically, preparing that
 output involves information loss, broken document structure

-or unintended formatting.
+or unintended formatting, no matter whether
+.Nm
+or GNU troff is used.
+In many cases, the output of
+.Nm
+and GNU troff is identical, but in some,
+.Nm
+is more resilient than GNU troff with respect to malformed input.
+.Pp
+Non-existent or unreadable input files are also reported on the
+.Cm error
+level.
+In that case, the parser cannot even be started and no output
+is produced from those input files.

 .It Cm warning
 An input file uses obsolete, discouraged or non-portable syntax.
 All the same, the meaning of the input is unambiguous and a correct
 .It Cm warning
 An input file uses obsolete, discouraged or non-portable syntax.
 All the same, the meaning of the input is unambiguous and a correct


@@ -624,10 +648,12 @@ formatting tools instead of
 .El
 .Pp
 Messages of the
 .El
 .Pp
 Messages of the

-.Cm warning
+.Cm warning ,
+.Cm error ,

 and
 and

-.Cm error
-levels are hidden unless their level, or a lower level, is requested using a
+.Cm unsupp
+levels except those about non-existent or unreadable input files
+are hidden unless their level, or a lower level, is requested using a

 .Fl W
 option or
 .Fl T Ns Cm lint
 .Fl W
 option or
 .Fl T Ns Cm lint


@@ -1256,9 +1282,6 @@ keeps the code more readable.
 .El
 .Ss "Errors related to tables"
 .Bl -inset -compact
 .El
 .Ss "Errors related to tables"
 .Bl -inset -compact

-.It "bad table syntax"
-.It "bad table option"
-.It "bad table layout"

 .It "no table layout cells specified"
 .It "no table data cells specified"
 .It "ignore data in cell"
 .It "no table layout cells specified"
 .It "no table data cells specified"
 .It "ignore data in cell"


@@ -1305,6 +1328,11 @@ or
 macro.
 It may be mistyped or unsupported.
 The request or macro is discarded including its arguments.
 macro.
 It may be mistyped or unsupported.
 The request or macro is discarded including its arguments.

+.It Sy "skipping insecure request"
+.Pq roff
+An input file attempted to run a shell command
+or to read or write an external file.
+Such attempts are denied for security reasons.

 .It Sy "skipping item outside list"
 .Pq mdoc , eqn
 An
 .It Sy "skipping item outside list"
 .Pq mdoc , eqn
 An


@@ -1455,6 +1483,29 @@ or
 .Ic \&gsize
 statement has a non-numeric or negative argument or no argument at all.
 The invalid request or statement is ignored.
 .Ic \&gsize
 statement has a non-numeric or negative argument or no argument at all.
 The invalid request or statement is ignored.

+.It Sy "NOT IMPLEMENTED: .so with absolute path or \(dq..\(dq"
+.Pq roff
+For security reasons,
+.Nm
+allows
+.Ic \&so
+file inclusion requests only with relative paths
+and only without ascending to any parent directory.
+By requesting the inclusion of a sensitive file, a malicious document
+might otherwise trick a privileged user into inadvertently displaying
+the file on the screen, revealing the file content to bystanders.
+.Nm
+only shows the path as it appears behind
+.Ic \&so .
+.It Sy ".so request failed"
+.Pq roff
+Servicing a
+.Ic \&so
+request requires reading an external file, but the file could not be
+opened.
+.Nm
+only shows the path as it appears behind
+.Ic \&so .

 .It Sy "skipping all arguments"
 .Pq mdoc , man , eqn , roff
 An
 .It Sy "skipping all arguments"
 .Pq mdoc , man , eqn , roff
 An


@@ -1494,7 +1545,7 @@ macro is invoked with more than one argument, or a request of the
 family is invoked with more than two arguments.
 The excess arguments are ignored.
 .El
 family is invoked with more than two arguments.
 The excess arguments are ignored.
 .El

-.Ss FATAL errors
+.Ss Unsupported features

 .Bl -ohang
 .It Sy "input too large"
 .Pq mdoc , man
 .Bl -ohang
 .It Sy "input too large"
 .Pq mdoc , man


@@ -1504,33 +1555,18 @@ cannot handle input files larger than its arbitrary size limit
 of 2^31 bytes (2 Gigabytes).
 Since useful manuals are always small, this is not a problem in practice.
 Parsing is aborted as soon as the condition is detected.
 of 2^31 bytes (2 Gigabytes).
 Since useful manuals are always small, this is not a problem in practice.
 Parsing is aborted as soon as the condition is detected.

-.It Sy "NOT IMPLEMENTED: .so with absolute path or \(dq..\(dq"
-.Pq roff
-For security reasons,
-.Nm
-allows
-.Ic \&so
-file inclusion requests only with relative paths
-and only without ascending to any parent directory.
-By requesting the inclusion of a sensitive file, a malicious document
-might otherwise trick a privileged user into inadvertently displaying
-the file on the screen, revealing the file content to bystanders.
-The parser exits immediately.
-.It Sy ".so request failed"
+.It Sy "unsupported roff request"

 .Pq roff
 .Pq roff

-Servicing a
-.Ic \&so
-request requires reading an external file.
-While trying to do so, an
-.Xr open 2 ,
-.Xr stat 2 ,
-or
-.Xr read 2
-system call failed.
-The parser exits immediately.
-Before showing this message,
-.Nm
-always shows another message explaining why the system call failed.
+An input file contains a
+.Xr roff 7
+request supported by GNU troff or Heirloom troff but not by
+.Nm ,
+and it is likely that this will cause information loss
+or considerable misformatting.
+.It Sy "bad table syntax"
+.It Sy "bad table option"
+.It Sy "bad table layout"
+.It Sy "ignoring macro in table"

 .El
 .Sh COMPATIBILITY
 This section summarises
 .El
 .Sh COMPATIBILITY
 This section summarises