resize1

Usage

Overview

Resize prints a shell command for setting the appropriate environment variables to indicate the current size of xterm window from which the command is run.

Resize determines the command through several steps:

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first, it finds the name of the user's shell program. It uses the SHELL variable if set, otherwise it uses the user's data from /etc/passwd.

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then it decides whether to use Bourne shell syntax or C-Shell syntax. It uses a built-in table of known shells, which can be overridden by the -u and -c options.

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then resize asks the operating system for the terminal settings. This is the same information which can be manipulated using stty.

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then resize asks the terminal for its size in characters. Depending on whether the "-s option is given, resize uses a different escape sequence to ask for this information.

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at this point, resize attempts to update the terminal settings to reflect the terminal window's size in pixels:

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if the -s option is used, resize then asks the terminal for its size in pixels.

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otherwise, resize asks the operating system for the information and updates that after ensuring that the window's dimensions are a multiple of the character height and width.

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in either case, the updated terminal settings are done using a different system call than used for stty.

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then resize updates the terminal settings to reflect any altered values such as its size in rows or columns. This affects the values shown by stty.

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finally, resize generates shell commands for setting the environment variables, and writes that to the standard output.

Options

The following options may be used with resize:

-c

This option indicates that C shell commands should be generated even if the user's current shell does not appear to use C shell syntax.

-s [rows columns]

This option indicates that Sun console escape sequences will be used instead of the VT100-style xterm escape codes. If rows and columns are given, resize will ask the xterm to resize itself using those values.

Both of the escape sequences used for this option (first to obtain the window size and second to modify it) are subject to xterm's allowWindowOps resource setting. The window manager may also choose to disallow the change.

The VT100-style escape sequence used to determine the screen size always works for VT100-compatible terminals. VT100s have no corresponding way to modify the screensize.

-u

This option indicates that Bourne shell commands should be generated even if the user's current shell does not appear to use Bourne shell syntax.

-v

This causes resize to print a version number to the standard output, and then exit.

Note that the Sun console escape sequences are recognized by XFree86 xterm and by dtterm. The resize program may be installed as sunsize, which causes makes it assume the -s option.

The rows and columns arguments must appear last; though they are normally associated with the -s option, they are parsed separately.

Environment

SHELL

Unless overridden by the -c option, resize determines the user's current shell by

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first checking if $SHELL is set, and using that,

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otherwise resize looks in the password file (/etc/passwd).

Generally Bourne-shell variants (including ksh) do not modify $SHELL, so it is possible for resize to be confused if one runs resize from a Bourne shell spawned from a C shell.

After determining the user's shell, resize checks the shell's name against a table of known shell names. If it does not find the name in its table, resize will use C shell syntax for the generated commands to set environment variables.

TERM

Resize's generated shell command sets this to "xterm" if not already set.

TERMCAP

Resize's generated shell command sets this variable on systems using termcap, e.g., when resize is linked with the termcap library rather than a terminfo library. The latter does not provide the complete text for a termcap entry.

COLUMNS, LINES

Resize's generated shell command sets these variables on systems using terminfo. Many applications (including the curses library) use those variables when set to override their screensize.

Files

/etc/termcap

for the base termcap entry to modify.

~/.cshrc

user's alias for the command.

Examples

For resize's output to take effect, resize must either be evaluated as part of the command line (usually done with a shell alias or function) or else redirected to a file which can then be read in. From the C shell (usually known as /bin/csh), the following alias could be defined in the user's .cshrc:

% alias rs 'set noglob; eval `resize`'

After resizing the window, the user would type:

% rs

Users of versions of the Bourne shell (usually known as /bin/sh) that don't have command functions will need to send the output to a temporary file and then read it back in with the “.” command:

$ resize > /tmp/out
$ . /tmp/out