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DELAY(1)                       OneGeek Software                       DELAY(1)

NAME

delay - counts down a specified number of seconds.

SYNOPSIS

delay [options] <length> [-- command] delay [options] until <timespec> [-- command]

DESCRIPTION

The delay program counts down a length of time specified on the command line. By default, it prints out the time remaining once a second. The rate and style of printing can be controlled using options to the program. This includes the ability to supress the printing entirely. It also somewhat supports delaying for fractional seconds. Delay attempts to compensate for the time it spends printing the updates. There should be no error that is a multiple of the time spent delaying. (There is a bit of error on the startup and termination of the program, but that's unavoidable.) There are several ways that the time to delay can be specified. The first is that it can be specified as an absolute length of time to delay. This can be in several formats. All of the following formats are allowable. (And equivalent.) delay 1d 2:03:04.5 delay 1d 2h 3m 4.5s delay 93785.5 Please note that the fractional seconds code will only work for actual fractional seconds. So, doing things like '0.5h' will delay for half a second, and not for half an hour as one may expect. (But don't rely on this behavior, as it may change in future versions.) The second format is for a time to delay until be specified. The time parsing code is derived from that used it at, and as a result the time specifications should be described on at(1). For example: delay until 4 pm delay until noon tomorrow delay until midnight 13 september 2000 delay until now + 5 minutes Please note that the parsing code has a resolution of a minute. So, the last specification would calculate the 5 minutes from the beginning of the current minute, and delay to that absolute point in time. If you need more precision, you can use the first time format, which allows an the delay length to be specified precisely. If delay sees "--" while parsing it's command line, it stops argument processing. Instead, the argument after the "--" is interpreted as a command to be run when delay completes, and any further arguments are used as arguments to that command. For example: delay until 9:30 -- cdplay

OPTIONS

Delay allows you to use command line options to control aspects of its behavior. Here's a list: -q This enables quiet mode. This prevents delay from outputting the time remaining as it usually does. (This is the default if delay is called with "sleep" as part of the program name.) -m This enables a minimalistic count of the time remaining, with only the number of seconds left being displayed. This was the default for delay 1.0. -d This enables the default display. The day, hour, minute, and second are all broken out into seperate entrys. (This is the default, except for the cases where -q is the default.) -v This enables a more verbose mode of display. (It adds some explanitory text, as compared to -d.) -c This allows you to specify a custom time prompt. Printf-style formatting is performed, with the following being allowed as the possible percent substitutions: %d Days remaining %h Hours remaining (modulo 24) %m Minutes remaining (modulo 60) %s Seconds remaining (modulo 60) %n Total seconds remaining For best results, you'll want to make sure that your custom format stays the same length throughout the count. Printf-style formatting is done on these codes. Use of percent-codes other than the ones listed above will lead to undefined behavior. (Crashes, usually.) The following escapes are also supported: \n Newline \r Carriage Return \b Backspace \\ Backslash \% Percent Since the custom format no longer implicitly begins with a carriage return, it usually makes sense to either begin a custom code with \r or end it with \n. The standard formats can be expressed as custom codes. Here's a list of translations. -m \r% 8n -d \r% 3d %02h:%02m:%02s -v \rTime Remaining: %d days, %02h:%02m:%02s. -C This option enables the display of time remaining in big ugly curses numerals. This only displays the hours, minutes, and seconds remaining, although the number of hours to go may range above 24. -u This option takes a single parameter, the time in seconds between updates of the time remaining. It need not be a factor of the delay length. It defaults to 1 second, and must be at least that value. -b If this option is given, a bell character will be sent when time expires. This may be useful in cases where an xterm is send to de- iconify on a bell. -V If given, delay will display it's version and a short copyright message, and will then exit.

BUGS

The default format is only good for delays of less than 1000 days. Improper use of the -c option can lead to various problems, and may even have some security implications. execvp(2) is used to run the command, and this may run programs in the current directory rather than fully respecting your path. Please see execvp(2) for more details.

AUTHOR

Tom Rothamel <tom-delay@onegeek.org>

WEB SITE

The delay web site is located at: http://onegeek.org/~tom/software/delay/

SEE ALSO

sleep(1), printf(3), at(1) 3rd Berkeley Distribution 2002-02-09 DELAY(1) curs_util(3X) curs_util(3X)

NAME

delay_output, filter, flushinp, getwin, key_name, keyname, nofilter, putwin, unctrl, use_env, use_tioctl, wunctrl - miscellaneous curses utility routines

SYNOPSIS

#include <ncurses/curses.h> const char *unctrl(chtype c); wchar_t *wunctrl(cchar_t *c); const char *keyname(int c); const char *key_name(wchar_t w); void filter(void); void nofilter(void); void use_env(bool f); void use_tioctl(bool f); int putwin(WINDOW *win, FILE *filep); WINDOW *getwin(FILE *filep); int delay_output(int ms); int flushinp(void);

DESCRIPTION

unctrl The unctrl routine returns a character string which is a printable representation of the character c, ignoring attributes. Control characters are displayed in the ^X notation. Printing characters are displayed as is. The corresponding wunctrl returns a printable representation of a wide character. keyname/key_name The keyname routine returns a character string corresponding to the key c: o Printable characters are displayed as themselves, e.g., a one- character string containing the key. o Control characters are displayed in the ^X notation. o DEL (character 127) is displayed as ^?. o Values above 128 are either meta characters (if the screen has not been initialized, or if meta(3X) has been called with a TRUE parameter), shown in the M-X notation, or are displayed as themselves. In the latter case, the values may not be printable; this follows the X/Open specification. o Values above 256 may be the names of the names of function keys. o Otherwise (if there is no corresponding name) the function returns null, to denote an error. X/Open also lists an "UNKNOWN KEY" return value, which some implementations return rather than null. The corresponding key_name returns a character string corresponding to the wide-character value w. The two functions do not return the same set of strings; the latter returns null where the former would display a meta character. filter/nofilter The filter routine, if used, must be called before initscr or newterm are called. Calling filter causes these changes in initialization: o LINES is set to 1; o the capabilities clear, cud1, cud, cup, cuu1, cuu, vpa are disabled; o the capability ed is disabled if bce is set; o and the home string is set to the value of cr. The nofilter routine cancels the effect of a preceding filter call. That allows the caller to initialize a screen on a different device, using a different value of $TERM. The limitation arises because the filter routine modifies the in-memory copy of the terminal information. use_env The use_env routine, if used, should be called before initscr or newterm are called (because those compute the screen size). It modifies the way ncurses treats environment variables when determining the screen size. o Normally ncurses looks first at the terminal database for the screen size. If use_env was called with FALSE for parameter, it stops here unless use_tioctl was also called with TRUE for parameter. o Then it asks for the screen size via operating system calls. If successful, it overrides the values from the terminal database. o Finally (unless use_env was called with FALSE parameter), ncurses examines the LINES or COLUMNS environment variables, using a value in those to override the results from the operating system or terminal database. Ncurses also updates the screen size in response to SIGWINCH, unless overridden by the LINES or COLUMNS environment variables, use_tioctl The use_tioctl routine, if used, should be called before initscr or newterm are called (because those compute the screen size). After use_tioctl is called with TRUE as an argument, ncurses modifies the last step in its computation of screen size as follows: o checks if the LINES and COLUMNS environment variables are set to a number greater than zero. o for each, ncurses updates the corresponding environment variable with the value that it has obtained via operating system call or from the terminal database. o ncurses re-fetches the value of the environment variables so that it is still the environment variables which set the screen size. The use_env and use_tioctl routines combine as summarized here: use_env use_tioctl Summary ---------------------------------------------------------------- TRUE FALSE This is the default behavior. ncurses uses operating system calls unless overridden by $LINES or $COLUMNS environment variables. TRUE TRUE ncurses updates $LINES and $COLUMNS based on operating system calls. FALSE TRUE ncurses ignores $LINES and $COLUMNS, uses operating system calls to obtain size. FALSE FALSE ncurses relies on the terminal database to determine size. putwin/getwin The putwin routine writes all data associated with window (or pad) win into the file to which filep points. This information can be later retrieved using the getwin function. The getwin routine reads window related data stored in the file by putwin. The routine then creates and initializes a new window using that data. It returns a pointer to the new window. There are a few caveats: o the data written is a copy of the WINDOW structure, and its associated character cells. The format differs between the wide- character (ncursesw) and non-wide (ncurses) libraries. You can transfer data between the two, however. o the retrieved window is always created as a top-level window (or pad), rather than a subwindow. o the window's character cells contain the color pair value, but not the actual color numbers. If cells in the retrieved window use color pairs which have not been created in the application using init_pair, they will not be colored when the window is refreshed. delay_output The delay_output routine inserts an ms millisecond pause in output. This routine should not be used extensively because padding characters are used rather than a CPU pause. If no padding character is specified, this uses napms to perform the delay. flushinp The flushinp routine throws away any typeahead that has been typed by the user and has not yet been read by the program.

RETURN VALUE

Except for flushinp, routines that return an integer return ERR upon failure and OK (SVr4 specifies only "an integer value other than ERR") upon successful completion. Routines that return pointers return NULL on error. X/Open does not define any error conditions. In this implementation flushinp returns an error if the terminal was not initialized. putwin returns an error if the associated fwrite calls return an error.

PORTABILITY

filter The SVr4 documentation describes the action of filter only in the vaguest terms. The description here is adapted from the XSI Curses standard (which erroneously fails to describe the disabling of cuu). keyname The keyname function may return the names of user-defined string capabilities which are defined in the terminfo entry via the -x option of tic. This implementation automatically assigns at run-time keycodes to user-defined strings which begin with "k". The keycodes start at KEY_MAX, but are not guaranteed to be the same value for different runs because user-defined codes are merged from all terminal descriptions which have been loaded. The use_extended_names(3X) function controls whether this data is loaded when the terminal description is read by the library. nofilter/use_tioctl The nofilter and use_tioctl routines are specific to ncurses. They were not supported on Version 7, BSD or System V implementations. It is recommended that any code depending on ncurses extensions be conditioned using NCURSES_VERSION. putwin/getwin The putwin and getwin functions have several issues with portability: o The files written and read by these functions use an implementation-specific format. Although the format is an obvious target for standardization, it has been overlooked. Interestingly enough, according to the copyright dates in Solaris source, the functions (along with scr_init, etc.) originated with the University of California, Berkeley (in 1982) and were later (in 1988) incorporated into SVr4. Oddly, there are no such functions in the 4.3BSD curses sources. o Most implementations simply dump the binary WINDOW structure to the file. These include SVr4 curses, NetBSD and PDCurses, as well as older ncurses versions. This implementation (as well as the X/Open variant of Solaris curses, dated 1995) uses textual dumps. The implementations which use binary dumps use block-I/O (the fwrite and fread functions). Those that use textual dumps use buffered-I/O. A few applications may happen to write extra data in the file using these functions. Doing that can run into problems mixing block- and buffered-I/O. This implementation reduces the problem on writes by flushing the output. However, reading from a file written using mixed schemes may not be successful. unctrl/wunctrl The XSI Curses standard, Issue 4 describes these functions. It states that unctrl and wunctrl will return a null pointer if unsuccessful, but does not define any error conditions. This implementation checks for three cases: o the parameter is a 7-bit US-ASCII code. This is the case that X/Open Curses documented. o the parameter is in the range 128-159, i.e., a C1 control code. If use_legacy_coding(3X) has been called with a 2 parameter, unctrl returns the parameter, i.e., a one-character string with the parameter as the first character. Otherwise, it returns "~@", "~A", etc., analogous to "^@", "^A", C0 controls. X/Open Curses does not document whether unctrl can be called before initializing curses. This implementation permits that, and returns the "~@", etc., values in that case. o parameter values outside the 0 to 255 range. unctrl returns a null pointer. The strings returned by unctrl in this implementation are determined at compile time, showing C1 controls from the upper-128 codes with a "~" prefix rather than "^". Other implementations have different conventions. For example, they may show both sets of control characters with "^", and strip the parameter to 7 bits. Or they may ignore C1 controls and treat all of the upper-128 codes as printable. This implementation uses 8 bits but does not modify the string to reflect locale. The use_legacy_coding(3X) function allows the caller to change the output of unctrl. Likewise, the meta(3X) function allows the caller to change the output of keyname, i.e., it determines whether to use the "M-" prefix for "meta" keys (codes in the range 128 to 255). Both use_legacy_coding(3X) and meta(3X) succeed only after curses is initialized. X/Open Curses does not document the treatment of codes 128 to 159. When treating them as "meta" keys (or if keyname is called before initializing curses), this implementation returns strings "M-^@", "M-^A", etc. X/Open Curses documents unctrl as declared in <unctrl.h>, which ncurses does. However, ncurses' <curses.h> includes <unctrl.h>, matching the behavior of SVr4 curses. Other implementations may not do that. use_env/use_tioctl If ncurses is configured to provide the sp-functions extension, the state of use_env and use_tioctl may be updated before creating each screen rather than once only (curs_sp_funcs(3X)). This feature of use_env is not provided by other implementation of curses.

SEE ALSO

curses(3X), curs_initscr(3X), curs_inopts(3X), curs_kernel(3X), curs_scr_dump(3X), curs_sp_funcs(3X), curs_variables(3X), legacy_coding(3X). curs_util(3X)

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