Путеводитель по Руководству Linux

  User  |  Syst  |  Libr  |  Device  |  Files  |  Other  |  Admin  |  Head  |



   putp.3x    ( 3 )

интерфейсы библиотеки Сurses к базе данных terminfo (curses interfaces to terminfo database)

   Дубль

(статьи: curs_terminfo.3x - интерфейсы библиотеки Сurses к базе данных terminfo )

Имя (Name)

del_curterm, mvcur, putp, restartterm, set_curterm, setupterm, tigetflag, tigetnum, tigetstr, tiparm, tparm, tputs, vid_attr, vid_puts, vidattr, vidputs - curses interfaces to terminfo database


Синопсис (Synopsis)

#include <curses.h> #include <term.h>

TERMINAL *cur_term;

const char * const boolnames[]; const char * const boolcodes[]; const char * const boolfnames[]; const char * const numnames[]; const char * const numcodes[]; const char * const numfnames[]; const char * const strnames[]; const char * const strcodes[]; const char * const strfnames[];

int setupterm(const char *term, int filedes, int *errret); TERMINAL *set_curterm(TERMINAL *nterm); int del_curterm(TERMINAL *oterm); int restartterm(const char *term, int filedes, int *errret);

char *tparm(const char *str, ...); int tputs(const char *str, int affcnt, int (*putc)(int)); int putp(const char *str);

int vidputs(chtype attrs, int (*putc)(int)); int vidattr(chtype attrs); int vid_puts(attr_t attrs, short pair, void *opts, int (*putc)(int)); int vid_attr(attr_t attrs, short pair, void *opts);

int mvcur(int oldrow, int oldcol, int newrow, int newcol);

int tigetflag(const char *capname); int tigetnum(const char *capname); char *tigetstr(const char *capname);

char *tiparm(const char *str, ...);


Описание (Description)

These low-level routines must be called by programs that have to deal directly with the terminfo database to handle certain terminal capabilities, such as programming function keys. For all other functionality, curses routines are more suitable and their use is recommended.

None of these functions use (or are aware of) multibyte character strings such as UTF-8:

• capability names use the POSIX portable character set

• capability string values have no associated encoding; they are strings of 8-bit characters.

Initialization Initially, setupterm should be called. The high-level curses functions initscr and newterm call setupterm to initialize the low-level set of terminal-dependent variables [listed in terminfo(5)].

Applications can use the terminal capabilities either directly (via header definitions), or by special functions. The header files curses.h and term.h should be included (in this order) to get the definitions for these strings, numbers, and flags.

The terminfo variables lines and columns are initialized by setupterm as follows:

• If use_env(FALSE) has been called, values for lines and columns specified in terminfo are used.

• Otherwise, if the environment variables LINES and COLUMNS exist, their values are used. If these environment variables do not exist and the program is running in a window, the current window size is used. Otherwise, if the environment variables do not exist, the values for lines and columns specified in the terminfo database are used.

Parameterized strings should be passed through tparm to instantiate them. All terminfo strings (including the output of tparm) should be printed with tputs or putp. Call reset_shell_mode to restore the tty modes before exiting [see curs_kernel(3X)].

Programs which use cursor addressing should

• output enter_ca_mode upon startup and

• output exit_ca_mode before exiting.

Programs which execute shell subprocesses should

• call reset_shell_mode and output exit_ca_mode before the shell is called and

• output enter_ca_mode and call reset_prog_mode after returning from the shell.

The setupterm routine reads in the terminfo database, initializing the terminfo structures, but does not set up the output virtualization structures used by curses. These are its parameters:

term is the terminal type, a character string. If term is null, the environment variable TERM is used.

filedes is the file descriptor used for all output.

errret points to an optional location where an error status can be returned to the caller. If errret is not null, then setupterm returns OK or ERR and stores a status value in the integer pointed to by errret. A return value of OK combined with status of 1 in errret is normal.

If ERR is returned, examine errret:

1 means that the terminal is hardcopy, cannot be used for curses applications.

setupterm determines if the entry is a hardcopy type by checking the hc (hardcopy) capability.

0 means that the terminal could not be found, or that it is a generic type, having too little information for curses applications to run.

setupterm determines if the entry is a generic type by checking the gn (generic) capability.

-1 means that the terminfo database could not be found.

If errret is null, setupterm prints an error message upon finding an error and exits. Thus, the simplest call is:

setupterm((char *)0, 1, (int *)0);,

which uses all the defaults and sends the output to stdout.

The Terminal State The setupterm routine stores its information about the terminal in a TERMINAL structure pointed to by the global variable cur_term. If it detects an error, or decides that the terminal is unsuitable (hardcopy or generic), it discards this information, making it not available to applications.

If setupterm is called repeatedly for the same terminal type, it will reuse the information. It maintains only one copy of a given terminal's capabilities in memory. If it is called for different terminal types, setupterm allocates new storage for each set of terminal capabilities.

The set_curterm routine sets cur_term to nterm, and makes all of the terminfo boolean, numeric, and string variables use the values from nterm. It returns the old value of cur_term.

The del_curterm routine frees the space pointed to by oterm and makes it available for further use. If oterm is the same as cur_term, references to any of the terminfo boolean, numeric, and string variables thereafter may refer to invalid memory locations until another setupterm has been called.

The restartterm routine is similar to setupterm and initscr, except that it is called after restoring memory to a previous state (for example, when reloading a game saved as a core image dump). restartterm assumes that the windows and the input and output options are the same as when memory was saved, but the terminal type and baud rate may be different. Accordingly, restartterm saves various tty state bits, calls setupterm, and then restores the bits.

Formatting Output The tparm routine instantiates the string str with parameters pi. A pointer is returned to the result of str with the parameters applied. Application developers should keep in mind these quirks of the interface:

• Although tparm's actual parameters may be integers or strings, the prototype expects long (integer) values.

• Aside from the set_attributes (sgr) capability, most terminal capabilities require no more than one or two parameters.

• Padding information is ignored by tparm; it is interpreted by tputs.

• The capability string is null-terminated. Use '\200' where an ASCII NUL is needed in the output.

tiparm is a newer form of tparm which uses <stdarg.h> rather than a fixed-parameter list. Its numeric parameters are integers (int) rather than longs.

Output Functions The tputs routine applies padding information (i.e., by interpreting marker embedded in the terminfo capability such as '$<5>' as 5 milliseconds) to the string str and outputs it:

• The str parameter must be a terminfo string variable or the return value from tparm, tiparm, tgetstr, or tgoto.

The tgetstr and tgoto functions are part of the termcap interface, which happens to share this function name with the terminfo interface.

affcnt is the number of lines affected, or 1 if not applicable.

putc is a putchar-like routine to which the characters are passed, one at a time.

The putp routine calls tputs(str, 1, putchar). The output of putp always goes to stdout, rather than the filedes specified in setupterm.

The vidputs routine displays the string on the terminal in the video attribute mode attrs, which is any combination of the attributes listed in curses(3X). The characters are passed to the putchar-like routine putc.

The vidattr routine is like the vidputs routine, except that it outputs through putchar.

The vid_attr and vid_puts routines correspond to vidattr and vidputs, respectively. They use a set of arguments for representing the video attributes plus color, i.e.,

attrs of type attr_t for the attributes and

pair of type short for the color-pair number.

The vid_attr and vid_puts routines are designed to use the attribute constants with the WA_ prefix.

X/Open Curses reserves the opts argument for future use, saying that applications must provide a null pointer for that argument. As an extension, this implementation allows opts to be used as a pointer to int, which overrides the pair (short) argument.

The mvcur routine provides low-level cursor motion. It takes effect immediately (rather than at the next refresh).

While putp and mvcur are low-level functions which do not use the high-level curses state, they are declared in <curses.h> because SystemV did this (see HISTORY).

Terminal Capability Functions The tigetflag, tigetnum and tigetstr routines return the value of the capability corresponding to the terminfo capname passed to them, such as xenl. The capname for each capability is given in the table column entitled capname code in the capabilities section of terminfo(5).

These routines return special values to denote errors.

The tigetflag routine returns

-1 if capname is not a boolean capability, or

0 if it is canceled or absent from the terminal description.

The tigetnum routine returns

-2 if capname is not a numeric capability, or

-1 if it is canceled or absent from the terminal description.

The tigetstr routine returns

(char *)-1 if capname is not a string capability, or

0 if it is canceled or absent from the terminal description.

Terminal Capability Names These null-terminated arrays contain

• the short terminfo names ('codes'),

• the termcap names ('names'), and

• the long terminfo names ('fnames')

for each of the predefined terminfo variables:

const char *boolnames[], *boolcodes[], *boolfnames[] const char *numnames[], *numcodes[], *numfnames[] const char *strnames[], *strcodes[], *strfnames[]