![我如何改变 CentOS7 上 **clear** 的行为,以使其不会清除 xterm 上的回滚缓冲区?](https://linux22.com/image/1498216/%E6%88%91%E5%A6%82%E4%BD%95%E6%94%B9%E5%8F%98%20CentOS7%20%E4%B8%8A%20**clear**%20%E7%9A%84%E8%A1%8C%E4%B8%BA%EF%BC%8C%E4%BB%A5%E4%BD%BF%E5%85%B6%E4%B8%8D%E4%BC%9A%E6%B8%85%E9%99%A4%20xterm%20%E4%B8%8A%E7%9A%84%E5%9B%9E%E6%BB%9A%E7%BC%93%E5%86%B2%E5%8C%BA%EF%BC%9F.png)
我正在运行一个虚拟机CentOs 7.2.1511。 这包括ncurses 5.9。我同时使用 MobaXterm 和 PuTTY。
每当我运行清除命令,回滚缓冲区也会自动清除。
在 ncurses 5.7(在另一个 CentOs VM CentOS 版本 6.5(最终版)上)中没有观察到这种行为。
阅读 ncurses 更新日志,进行了一项更改,以便 ncurses 考虑到“清除终端回滚缓冲区的 E3 扩展功能”
手册页还提到了 terminfo:
它在环境中查找终端类型,然后在terminfo 数据库弄清楚如何清除屏幕。
所以术语信息有数据清除用来决定是否应该清除终端的回滚缓冲区。我找到了一个实用程序,信息流,可以打印出terminfo的描述。
信息流
姓名
infocmp - compare or print out terminfo descriptions
我已将输出放在下面的详细信息中。
terminfo 中的“clear”条目显示“clear=\E[H\E[2J,”。
当我跑步时清除在CentOS7VM 我看到了这一点(完整的 strace 如下,详情如下)
write(1, "\33[3;J\33[H\33[2J", 12
) = 12
当我跑步时清除在CentOS6.5VM 我看到了
write(1, "\33[H\33[2J", 7
)
我认为新版本清除从某个地方拾取一些东西,告诉它添加“\33[3;J“。(这可能就是变更日志中提到的变更)
但正如手册页所述;该信息是从术语信息。我的 terminfo clear 条目没有\33[3;J\33[H\33[2J;相反,它有\33[H\33[2J。
所以;如果我遗漏了某些东西,而这不是 ncurses 5.9 中的错误;
我如何改变清除在 Centos7 上不清除回滚缓冲区?
我不是想修改代码并进行编译,也不是想用 5.7 替换 5.9。
谢谢你们
细节:
操作系统:CentOS Linux 版本 7.2.1511(核心) ncurses:ncurses 版本 5.9(补丁 20130511)[取自“man clear”]
CentOS 7 上 infocmp 的输出:
# infocmp
# Reconstructed via infocmp from file: /usr/share/terminfo/x/xterm
xterm|xterm terminal emulator (X Window System),
am, bce, km, mc5i, mir, msgr, npc, xenl,
colors#8, cols#80, it#8, lines#24, pairs#64,
acsc=``aaffggiijjkkllmmnnooppqqrrssttuuvvwwxxyyzz{{||}}~~,
bel=^G, blink=\E[5m, bold=\E[1m, cbt=\E[Z, civis=\E[?25l,
clear=\E[H\E[2J, cnorm=\E[?12l\E[?25h, cr=^M,
csr=\E[%i%p1%d;%p2%dr, cub=\E[%p1%dD, cub1=^H,
cud=\E[%p1%dB, cud1=^J, cuf=\E[%p1%dC, cuf1=\E[C,
cup=\E[%i%p1%d;%p2%dH, cuu=\E[%p1%dA, cuu1=\E[A,
cvvis=\E[?12;25h, dch=\E[%p1%dP, dch1=\E[P, dl=\E[%p1%dM,
dl1=\E[M, ech=\E[%p1%dX, ed=\E[J, el=\E[K, el1=\E[1K,
flash=\E[?5h$<100/>\E[?5l, home=\E[H, hpa=\E[%i%p1%dG,
ht=^I, hts=\EH, ich=\E[%p1%d@, il=\E[%p1%dL, il1=\E[L,
ind=^J, indn=\E[%p1%dS, invis=\E[8m,
is2=\E[!p\E[?3;4l\E[4l\E>, kDC=\E[3;2~, kEND=\E[1;2F,
kHOM=\E[1;2H, kIC=\E[2;2~, kLFT=\E[1;2D, kNXT=\E[6;2~,
kPRV=\E[5;2~, kRIT=\E[1;2C, kb2=\EOE, kbs=\177, kcbt=\E[Z,
kcub1=\EOD, kcud1=\EOB, kcuf1=\EOC, kcuu1=\EOA,
kdch1=\E[3~, kend=\EOF, kent=\EOM, kf1=\EOP, kf10=\E[21~,
kf11=\E[23~, kf12=\E[24~, kf13=\E[1;2P, kf14=\E[1;2Q,
kf15=\E[1;2R, kf16=\E[1;2S, kf17=\E[15;2~, kf18=\E[17;2~,
kf19=\E[18;2~, kf2=\EOQ, kf20=\E[19;2~, kf21=\E[20;2~,
kf22=\E[21;2~, kf23=\E[23;2~, kf24=\E[24;2~,
kf25=\E[1;5P, kf26=\E[1;5Q, kf27=\E[1;5R, kf28=\E[1;5S,
kf29=\E[15;5~, kf3=\EOR, kf30=\E[17;5~, kf31=\E[18;5~,
kf32=\E[19;5~, kf33=\E[20;5~, kf34=\E[21;5~,
kf35=\E[23;5~, kf36=\E[24;5~, kf37=\E[1;6P, kf38=\E[1;6Q,
kf39=\E[1;6R, kf4=\EOS, kf40=\E[1;6S, kf41=\E[15;6~,
kf42=\E[17;6~, kf43=\E[18;6~, kf44=\E[19;6~,
kf45=\E[20;6~, kf46=\E[21;6~, kf47=\E[23;6~,
kf48=\E[24;6~, kf49=\E[1;3P, kf5=\E[15~, kf50=\E[1;3Q,
kf51=\E[1;3R, kf52=\E[1;3S, kf53=\E[15;3~, kf54=\E[17;3~,
kf55=\E[18;3~, kf56=\E[19;3~, kf57=\E[20;3~,
kf58=\E[21;3~, kf59=\E[23;3~, kf6=\E[17~, kf60=\E[24;3~,
kf61=\E[1;4P, kf62=\E[1;4Q, kf63=\E[1;4R, kf7=\E[18~,
kf8=\E[19~, kf9=\E[20~, khome=\EOH, kich1=\E[2~,
kind=\E[1;2B, kmous=\E[M, knp=\E[6~, kpp=\E[5~,
kri=\E[1;2A, mc0=\E[i, mc4=\E[4i, mc5=\E[5i, meml=\El,
memu=\Em, op=\E[39;49m, rc=\E8, rev=\E[7m, ri=\EM,
rin=\E[%p1%dT, rmacs=\E(B, rmam=\E[?7l, rmcup=\E[?1049l,
rmir=\E[4l, rmkx=\E[?1l\E>, rmm=\E[?1034l, rmso=\E[27m,
rmul=\E[24m, rs1=\Ec, rs2=\E[!p\E[?3;4l\E[4l\E>, sc=\E7,
setab=\E[4%p1%dm, setaf=\E[3%p1%dm,
setb=\E[4%?%p1%{1}%=%t4%e%p1%{3}%=%t6%e%p1%{4}%=%t1%e%p1%{6}%=%t3%e%p1%d%;m,
setf=\E[3%?%p1%{1}%=%t4%e%p1%{3}%=%t6%e%p1%{4}%=%t1%e%p1%{6}%=%t3%e%p1%d%;m,
sgr=%?%p9%t\E(0%e\E(B%;\E[0%?%p6%t;1%;%?%p2%t;4%;%?%p1%p3%|%t;7%;%?%p4%t;5%;%?%p7%t;8%;m,
sgr0=\E(B\E[m, smacs=\E(0, smam=\E[?7h, smcup=\E[?1049h,
smir=\E[4h, smkx=\E[?1h\E=, smm=\E[?1034h, smso=\E[7m,
smul=\E[4m, tbc=\E[3g, u6=\E[%i%d;%dR, u7=\E[6n,
u8=\E[?1;2c, u9=\E[c, vpa=\E[%i%p1%dd,
strace 清除:(CentOS7)
# strace clear
execve("/bin/clear", ["clear"], [/* 36 vars */]) = 0
brk(0) = 0xf60000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fd26198c000
access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=41031, ...}) = 0
mmap(NULL, 41031, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7fd261975000
close(3) = 0
open("/lib64/libtinfo.so.5", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0@\316\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=174520, ...}) = 0
mmap(NULL, 2268928, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fd261535000
mprotect(0x7fd26155a000, 2097152, PROT_NONE) = 0
mmap(0x7fd26175a000, 20480, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x25000) = 0x7fd261750
close(3) = 0
open("/lib64/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0 \34\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=2107816, ...}) = 0
mmap(NULL, 3932736, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fd26116d000
mprotect(0x7fd261323000, 2097152, PROT_NONE) = 0
mmap(0x7fd261523000, 24576, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1b6000) = 0x7fd26150
mmap(0x7fd261529000, 16960, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7fd261529000
close(3) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fd26198b000
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fd261989000
arch_prctl(ARCH_SET_FS, 0x7fd261989740) = 0
mprotect(0x7fd261523000, 16384, PROT_READ) = 0
mprotect(0x7fd26175a000, 16384, PROT_READ) = 0
mprotect(0x600000, 4096, PROT_READ) = 0
mprotect(0x7fd261986000, 4096, PROT_READ) = 0
munmap(0x7fd261975000, 41031) = 0
ioctl(1, SNDCTL_TMR_TIMEBASE or SNDRV_TIMER_IOCTL_NEXT_DEVICE or TCGETS, {B38400 opost isig icanon echo ...}) =0
brk(0) = 0xf60000
brk(0xf81000) = 0xf81000
brk(0) = 0xf81000
stat("/root/.terminfo", 0xf601c0) = -1 ENOENT (No such file or directory)
stat("/etc/terminfo", {st_mode=S_IFDIR|0755, st_size=6, ...}) = 0
stat("/usr/share/terminfo", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
access("/etc/terminfo/x/xterm", R_OK) = -1 ENOENT (No such file or directory)
access("/usr/share/terminfo/x/xterm", R_OK) = 0
open("/usr/share/terminfo/x/xterm", O_RDONLY) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=3371, ...}) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fd261985000
read(3, "\32\0010\0&\0\17\0\235\1l\5xterm|xterm terminal"..., 4096) = 3371
read(3, "", 4096) = 0
close(3) = 0
munmap(0x7fd261985000, 4096) = 0
ioctl(1, SNDCTL_TMR_TIMEBASE or SNDRV_TIMER_IOCTL_NEXT_DEVICE or TCGETS, {B38400 opost isig icanon echo ...}) =0
ioctl(1, SNDCTL_TMR_TIMEBASE or SNDRV_TIMER_IOCTL_NEXT_DEVICE or TCGETS, {B38400 opost isig icanon echo ...}) =0
ioctl(1, TIOCGWINSZ, {ws_row=62, ws_col=112, ws_xpixel=896, ws_ypixel=930}) = 0
fstat(1, {st_mode=S_IFCHR|0600, st_rdev=makedev(136, 0), ...}) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fd261985000
write(1, "\33[3;J\33[H\33[2J", 12
) = 12
exit_group(0) = ?
+++ exited with 0 +++
答案1
要查看的地方是延长-x
功能,使用选项显示infocmp
,例如,
infocmp -1x |grep E3
将显示
E3=\E[3J,
(我使用了-1
将输出格式化为单列的选项)。您可以像往常一样执行
infocmp -x >foo
vi foo # remove/adjust whatever
sudo tic -x foo
xterm
和linux
(Linux控制台)都支持此功能。
进一步阅读: