1TPUT(P)                    POSIX Programmer's Manual                   TPUT(P)
2
3
4

NAME

6       tput - change terminal characteristics
7

SYNOPSIS

9       tput [-T type] operand...
10

DESCRIPTION

12       The  tput  utility  shall  display terminal-dependent information.  The
13       manner in which this  information  is  retrieved  is  unspecified.  The
14       information  displayed  shall clear the terminal screen, initialize the
15       user's terminal, or reset the user's terminal, depending on the operand
16       given.  The  exact  consequences  of  displaying  this  information are
17       unspecified.
18

OPTIONS

20       The tput utility shall  conform  to  the  Base  Definitions  volume  of
21       IEEE Std 1003.1-2001, Section 12.2, Utility Syntax Guidelines.
22
23       The following option shall be supported:
24
25       -T  type
26              Indicate  the  type  of terminal. If this option is not supplied
27              and the TERM variable is unset or null, an  unspecified  default
28              terminal  type  shall  be  used.  The setting of type shall take
29              precedence over the value in TERM .
30
31

OPERANDS

33       The following strings shall be supported as operands by the implementa‐
34       tion in the POSIX locale:
35
36       clear  Display the clear-screen sequence.
37
38       init   Display  the sequence that initializes the user's terminal in an
39              implementation-defined manner.
40
41       reset  Display the sequence that  resets  the  user's  terminal  in  an
42              implementation-defined manner.
43
44
45       If a terminal does not support any of the operations described by these
46       operands, this shall not be considered an error condition.
47

STDIN

49       Not used.
50

INPUT FILES

52       None.
53

ENVIRONMENT VARIABLES

55       The following environment variables shall affect the execution of tput:
56
57       LANG   Provide a default value for the  internationalization  variables
58              that  are  unset  or  null.  (See the Base Definitions volume of
59              IEEE Std 1003.1-2001, Section  8.2,  Internationalization  Vari‐
60              ables  for the precedence of internationalization variables used
61              to determine the values of locale categories.)
62
63       LC_ALL If set to a non-empty string value, override the values  of  all
64              the other internationalization variables.
65
66       LC_CTYPE
67              Determine  the  locale  for  the  interpretation of sequences of
68              bytes of text data as characters (for  example,  single-byte  as
69              opposed to multi-byte characters in arguments).
70
71       LC_MESSAGES
72              Determine  the  locale  that should be used to affect the format
73              and contents of diagnostic messages written to standard error.
74
75       NLSPATH
76              Determine the location of message catalogs for the processing of
77              LC_MESSAGES .
78
79       TERM   Determine  the terminal type. If this variable is unset or null,
80              and if the -T option is not specified,  an  unspecified  default
81              terminal type shall be used.
82
83

ASYNCHRONOUS EVENTS

85       Default.
86

STDOUT

88       If standard output is a terminal device, it may be used for writing the
89       appropriate sequence to clear the screen or  reset  or  initialize  the
90       terminal.  If  standard  output  is  not  a  terminal device, undefined
91       results occur.
92

STDERR

94       The standard error shall be used only for diagnostic messages.
95

OUTPUT FILES

97       None.
98

EXTENDED DESCRIPTION

100       None.
101

EXIT STATUS

103       The following exit values shall be returned:
104
105        0     The requested string was written successfully.
106
107        1     Unspecified.
108
109        2     Usage error.
110
111        3     No information is available about the specified terminal type.
112
113        4     The specified operand is invalid.
114
115       >4     An error occurred.
116
117

CONSEQUENCES OF ERRORS

119       If one of the operands is not available for the terminal, tput  contin‐
120       ues processing the remaining operands.
121
122       The following sections are informative.
123

APPLICATION USAGE

125       The  difference  between  resetting and initializing a terminal is left
126       unspecified, as they vary greatly based on hardware types.  In general,
127       resetting is a more severe action.
128
129       Some  terminals use control characters to perform the stated functions,
130       and on such terminals it might make sense to use tput to store the ini‐
131       tialization  strings  in  a file or environment variable for later use.
132       However, because other terminals might rely on system calls to do  this
133       work,  the standard output cannot be used in a portable manner, such as
134       the following non-portable constructs:
135
136
137              ClearVar=`tput clear`
138              tput reset | mailx -s "Wake Up" ddg
139

EXAMPLES

141        1. Initialize the terminal according to the type of  terminal  in  the
142           environmental  variable  TERM  .  This command can be included in a
143           .profile file.
144
145
146           tput init
147
148        2. Reset a 450 terminal.
149
150
151           tput -T 450 reset
152

RATIONALE

154       The list of operands was reduced to a minimum for  the  following  rea‐
155       sons:
156
157        * The  only  features chosen were those that were likely to be used by
158          human users interacting with a terminal.
159
160        * Specifying the full terminfo set was not considered  desirable,  but
161          the standard developers did not want to select among operands.
162
163        * This  volume  of  IEEE Std 1003.1-2001  does  not attempt to provide
164          applications with sophisticated terminal handling  capabilities,  as
165          that  falls  outside  of  its assigned scope and intersects with the
166          responsibilities of other standards bodies.
167
168       The difference between resetting and initializing a  terminal  is  left
169       unspecified  as  this  varies greatly based on hardware types.  In gen‐
170       eral, resetting is a more severe action.
171
172       The exit status of 1 is historically reserved  for  finding  out  if  a
173       Boolean  operand  is  not  set. Although the operands were reduced to a
174       minimum, the exit status of 1 should still be reserved for the  Boolean
175       operands, for those sites that wish to support them.
176

FUTURE DIRECTIONS

178       None.
179

SEE ALSO

181       stty , tabs
182
184       Portions  of  this text are reprinted and reproduced in electronic form
185       from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
186       --  Portable  Operating  System  Interface (POSIX), The Open Group Base
187       Specifications Issue 6, Copyright (C) 2001-2003  by  the  Institute  of
188       Electrical  and  Electronics  Engineers, Inc and The Open Group. In the
189       event of any discrepancy between this version and the original IEEE and
190       The  Open Group Standard, the original IEEE and The Open Group Standard
191       is the referee document. The original Standard can be  obtained  online
192       at http://www.opengroup.org/unix/online.html .
193
194
195
196IEEE/The Open Group                  2003                              TPUT(P)
Impressum