terminfo参数化字符串的延迟

时间:2017-12-15 15:03:28

标签: python terminal ncurses terminfo termcap

在terminfo的联机帮助页中,提到用于指定$<>中的延迟的编码中的ms,并且在其内部的尖括号中是具有最多一个小数位精度的数字。 / p>

使用以下python脚本,我确认$<仅用于指定延迟,即没有参数化字符串,其中$<已被用于未指定延迟。

#!/usr/bin/env python3
# './test/data/stressTestTerms.txt' contains contains terminal names
# and directory './test/data/mirror' contains terminal databases of 2718 terminals

import subprocess
import re


def check_dollar_angular(caps):
    string_caps = [cap for cap in caps.split(',') if '=' in cap]

    # search for $<..> type delays in string caps
    delay = r"\$<(\d+(\.(\d)+)?\*?/?|(\.(\d)+)?\*?/?)>"

    caps_with_dollar = 0
    delay_matches = 0

    for cap in string_caps:
        matches = list(re.finditer(delay, cap))
        dollar_idx = cap.find('$<')

        if dollar_idx != -1:
            caps_with_dollar += 1
            if any([True if match.start() == dollar_idx else False for match in matches]):
                delay_matches += 1

    if caps_with_dollar == delay_matches:
        return True
    else:
        return False


if __name__ == "__main__":

    with open('./test/data/stressTestTerms.txt') as terminal_names:
        res = []

        for each_terminal in terminal_names:
            output = subprocess.run(
                ['infocmp', '-0', '-A', './test/data/mirror', each_terminal.strip()], stdout=subprocess.PIPE)

            try:
                output.check_returncode()
                caps = output.stdout.decode('utf-8')

                res.append(check_dollar_angular(caps))

            except subprocess.CalledProcessError as e:
                print(e)

        if (not all(res)):
            print(
                "We have a terminal where in one of it's caps there is a dollar-angular but it doesn't signify delay")
        else:
            print(
                "Success! no terminal found where '$<' is used for anything else other than specifying delay")

所以我的问题是, $<是否属于文本/序列并且不代表延迟?例如。可以有一个案例(现在或将来的终端),如:$<%p1%d$<A,其中没有结束角括号,延迟不是要使用$<来指定仍然是有效的terminfo序列?

1 个答案:

答案 0 :(得分:2)

manual page非常清楚语法:

   A  delay  in  milliseconds  may appear anywhere in a string capability,
   enclosed in $<..> brackets, as in el=\EK$<5>,  and  padding  characters
   are supplied by tputs(3x) to provide this delay.

   o   The delay must be a number with at most one decimal place of preci-
       sion; it may be followed by suffixes "*" or "/" or both.

   o   A "*" indicates that the padding required is  proportional  to  the
       number  of lines affected by the operation, and the amount given is
       the per-affected-unit padding required.  (In  the  case  of  insert
       character, the factor is still the number of lines affected.)

       Normally, padding is advisory if the device has the xon capability;
       it is used for cost computation but does not trigger delays.

   o   A "/" suffix indicates that the padding is mandatory and  forces  a
       delay of the given number of milliseconds even on devices for which
       xon is present to indicate flow control.

如果没有结尾 < ,并且所附文字不是有效数字(可能 * 和/或 / ),然后tputs不应将其视为延迟。

没有示例 $< 后面没有数字或&#34;。&#34;在ncurses的终端数据库中,但这并不意味着它会无效,因为终端数据库应该能够描述大多数字符串(除了 {{1}的特殊情况(八进制)与 \200 的处理方式相同,以适应C语言的NUL终止字符串。