我想编写一个 perl 脚本，将一系列消息打印到终端。
我希望能够在这些消息之间导航。过去，我输入“>”之类的内容来向前移动消息，输入“<”来向后移动消息。但是，这次我想做一些不同的事情，使用“tab”向前移动消息，使用“shift-tab”向后移动消息。
然而，Perl 似乎将“shift-tab”读作“esc”键。如何在 Perl 中捕获有关修饰键的信息？
这是我编写的一段测试代码，用于检测用户在提示符下输入的内容。
#!/usr/bin/perl
use strict;
use warnings;
use Term::ReadKey;
my $response = "";
my $continue = 0;
eval {
local $SIG{ALRM} = sub {
ReadMode 'normal';
print "\n ... timed out ...\n";
die 'Timed Out';
};
ReadMode 'cbreak';
while ( $continue == 0 )
{
alarm 4;
print "Enter your key: ";
my $key = Term::ReadKey::ReadKey(0);
$response = $key;
KEY:{
if ( $key eq "\n" ) { print "return entered\n"; $continue = 1; last KEY;}
if ( $key eq "\t" ) { print "tab entered\n"; last KEY;}
if ( $key eq "\e" ) { print "escape entered\n"; last KEY;}
if ( $key eq "\x7f" ) { print "backspace entered\n"; last KEY;}
if ( $key eq ">" ) { print "forward page\n"; last KEY;}
if ( $key eq "<" ) { print "forward page\n"; last KEY;}
print "You entered something else\n";
}
}
ReadMode(0) ;
}
实际上，上面的代码向我揭示了一些东西。也就是说，当我输入某些键时，它们不会被读取为单个键，而是被读取为一系列键。因此，shift-tab 被读取为 \e[Z。现在，我想知道如何处理这个问题。有什么建议么？有没有办法区分用户输入 \e 和发送 \e[Z 的按键(如 shift-tab)？
最佳答案
遵循PerlMonks discussion根据@choroba的建议，我采用了以下方法来设置读取键序列的超时阈值。
这是我的代码，其中添加了很多内容，但主要的代码指出以转义开头的序列是否已发出信号，然后设置超时以读取按键序列的其余部分。
我怀疑其中的某些方面可能是我的终端设置所特有的；我还没有花时间去探索这个问题。
#!/usr/bin/perl
use strict;
use warnings;
use Term::ReadKey;
use Time::HiRes qw/usleep ualarm/;
my $continue = 0;
eval {
local $SIG{ALRM} = sub {
ReadMode 'normal';
print "\n ... timed out ...\n";
die 'Timed Out';
};
ReadMode 'cbreak';
while ( $continue == 0 )
{
print "Enter your key: ";
my $key = "";
my $alt = "";
$key = Term::ReadKey::ReadKey(0);
if ( $key eq "\e" )
{
eval {
local $SIG{ALRM} = sub {
## print "too fast\n";
die "";
};
ualarm(100);
while ( 1 )
{
$key .= Term::ReadKey::ReadKey(0);
}
};
$alt = $key;
$alt =~ s/^\e/{E}/;
}
alarm 5;
KEY:{
if ( $key eq "\eOP" ) { printf "%8s -> %-7s \n" , "F1", $alt; last KEY; }
if ( $key eq "\eOQ" ) { printf "%8s -> %-7s \n" , "F2", $alt; last KEY; }
if ( $key eq "\eOR" ) { printf "%8s -> %-7s \n" , "F3", $alt; last KEY; }
if ( $key eq "\eOS" ) { printf "%8s -> %-7s \n" , "F4", $alt; last KEY; }
if ( $key eq "\e[15~" ) { printf "%8s -> %-7s \n" , "F5", $alt; last KEY; }
if ( $key eq "\e[17~" ) { printf "%8s -> %-7s \n" , "F6", $alt; last KEY; }
if ( $key eq "\e[18~" ) { printf "%8s -> %-7s \n" , "F7", $alt; last KEY; }
if ( $key eq "\e[19~" ) { printf "%8s -> %-7s \n" , "F8", $alt; last KEY; }
if ( $key eq "\e[20~" ) { printf "%8s -> %-7s \n" , "F9", $alt; last KEY; }
if ( $key eq "\e[21~" ) { printf "%8s -> %-7s \n" , "F10", $alt; last KEY; }
if ( $key eq "\e[23~" ) { printf "%8s -> %-7s \n" , "F11", $alt; last KEY; }
if ( $key eq "\e[24~" ) { printf "%8s -> %-7s \n" , "F12", $alt; last KEY; }
if ( $key eq "\e[25~" ) { printf "%8s -> %-7s \n" , "F13", $alt; last KEY; }
if ( $key eq "\e[26~" ) { printf "%8s -> %-7s \n" , "F14", $alt; last KEY; }
if ( $key eq "\e[28~" ) { printf "%8s -> %-7s \n" , "F15", $alt; last KEY; }
if ( $key eq "\e[29~" ) { printf "%8s -> %-7s \n" , "F16", $alt; last KEY; }
if ( $key eq "\e[31~" ) { printf "%8s -> %-7s \n" , "F17", $alt; last KEY; }
if ( $key eq "\e[32~" ) { printf "%8s -> %-7s \n" , "F18", $alt; last KEY; }
if ( $key eq "\e[Z" ) { printf "%8s -> %-7s \n" , "shft-tab", $alt; last KEY; }
if ( $key eq "\e[A" ) { printf "%8s -> %-7s \n" , "up", $alt; last KEY; }
if ( $key eq "\e[B" ) { printf "%8s -> %-7s \n" , "down", $alt; last KEY; }
if ( $key eq "\e[C" ) { printf "%8s -> %-7s \n" , "right", $alt; last KEY; }
if ( $key eq "\e[D" ) { printf "%8s -> %-7s \n" , "left", $alt; last KEY; }
if ( $key eq "\e[1;2D" ) { printf "%8s -> %-7s \n" , "sht-left", $alt; last KEY; }
if ( $key eq "\e[1;2C" ) { printf "%8s -> %-7s \n" , "sht-right", $alt; last KEY; }
if ( $key eq "\e[1;5D" ) { printf "%8s -> %-7s \n" , "cnt-left", $alt; last KEY; }
if ( $key eq "\e[1;5C" ) { printf "%8s -> %-7s \n" , "cnt-right", $alt; last KEY; }
if ( $key eq "\eb" ) { printf "%8s -> %-7s \n" , "opt-left", $alt; last KEY; }
if ( $key eq "\ef" ) { printf "%8s -> %-7s \n" , "opt-right", $alt; last KEY; }
if ( $key eq "\e" ) { printf "%8s -> %-7s\n", "ESC", "{E}"; last KEY;}
if ( $key eq "\n" ) { print "return entered\n"; $continue = 1; last KEY;}
if ( $key eq "\t" ) { print "tab entered\n"; last KEY;}
if ( $key eq "\x7f" ) { print "backspace entered\n"; last KEY;}
if ( $key eq ">" ) { print "forward page\n"; last KEY;}
if ( $key eq "<" ) { print "backward page\n"; last KEY;}
if ( $key =~ /^[a-zA-Z]$/ ) { printf "Alphabet \"%s\"\n",$key; last KEY; }
if ( $key =~ /^[[:digit:]]$/ ) { printf "Numeric \"%s\"\n",$key; last KEY; }
if ( $key =~ /^[[:punct:]]$/ ) { printf "Punctuation \"%s\"\n",$key; last KEY; }
if ( length($key) > 1 )
{
$key =~ s/^\e/{E}/;
printf "something long: \"%s\"\n",$key;
last KEY;
}
if ( ord($key) == 1 ) { print "Cntr-A (Start of heading)\n"; last KEY; }
if ( ord($key) == 2 ) { print "Cntr-B (Start of text)\n"; last KEY; }
if ( ord($key) == 3 ) { print "Cntr-C [=== quit your program ]\n"; last KEY; }
if ( ord($key) == 4 ) { print "Cntr-D [=== quit your terminal ]\n"; last KEY; }
if ( ord($key) == 5 ) { print "Cntr-E (Enquiry)\n"; last KEY; }
if ( ord($key) == 6 ) { print "Cntr-F (Acknowledge)\n"; last KEY; }
if ( ord($key) == 7 ) { print "Cntr-G (Ring terminal bell)\n"; last KEY; }
if ( ord($key) == 8 ) { print "Cntr-H (backspace)\n"; last KEY; }
print "You entered something else: $key\n";
}
}
ReadMode(0) ;
}
关于perl - 如何让 Perl 在读取用户输入时识别 Shift-Tab，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/71551032/