我的输出去哪了? - V2EX
V2EX = way to explore
V2EX 是一个关于分享和探索的地方
Sign Up Now
For Existing Member  Sign In
Distributions
Ubuntu
Fedora
CentOS
中文资源站
网易开源镜像站
liyongjun0803
V2EX    Linux

我的输出去哪了?

  •  
  •   liyongjun0803 Apr 23, 2020 3250 views
    This topic created in 2202 days ago, the information mentioned may be changed or developed.

    C 语言写了一个循环打印 hello world 的程序:

    #include <stdio.h> #include <unistd.h> int main(int argc, char argv[]) { while (1) { printf("#################################hello world\n"); sleep(1); } return 0; } 

    编译、放入 /usr/bin 目录、增加开机自启:

    $ gcc hello.c -o hello.out $ sudo cp hello.out /usr/bin/ $ cat /etc/rc5.d/S01hello #! /bin/sh /usr/bin/hello.out & 

    在开机自启里面我并没有将输出重定向到任何文件(不想加,做个实验),请问系统重启后,我这个后台运行的 /usr/bin/hello.out (PID = 535) 的输出去哪了?我还能找到它吗?

    $ ps -ef | grep hello root 535 1 0 15:21 ? 00:00:00 /usr/bin/hello.out 

    以下是我进行的尝试,既不懂,也没有效果。

    strace -p 535 -ewrite 
    sudo reptyr 535 -T 

    下面是 /proc 中 535 进程的文件描述符信息,我能从这里得到输出数据吗?这里的 'socket:[15354]' 我能使用吗?怎样使用?

    # cd /proc/535/fd root@liyongjun-VirtualBox:/proc/535/fd# ll 总用量 0 dr-x------ 2 root root 0 4 月 23 15:23 ./ dr-xr-xr-x 9 root root 0 4 月 23 15:22 ../ lr-x------ 1 root root 64 4 月 23 15:23 0 -> /dev/null lrwx------ 1 root root 64 4 月 23 15:23 1 -> 'socket:[15354]' lrwx------ 1 root root 64 4 月 23 15:23 2 -> 'socket:[15354]' 

    以上
    有没有大神指点一下?

    3 replies    2020-04-23 18:37:17 +08:00
    robot1
        1
    robot1  
       Apr 23, 2020
    不太懂 大概看了下,stdin,stdout,stderr 分别是 0,1,2 你程序的 1,2 都指向了 socket?你有重定向输出吗
    zdy349
        2
    zdy349  
       Apr 23, 2020
    /var/log/boot.log 里找找
    wsy2220
        3
    wsy2220  
       Apr 23, 2020
    重定向到 systemd-journald 了
    About     Help     Advertise     Blog     API     FAQ     Solana     2611 Online   Highest 6679       Select Language
    创意工作者们的社区
    World is powered by solitude
    VERSION: 3.9.8.5 63ms UTC 05:40 PVG 13:40 LAX 22:40 JFK 01:40
    Do have faith in what you're doing.
    ubao msn snddm index pchome yahoo rakuten mypaper meadowduck bidyahoo youbao zxmzxm asda bnvcg cvbfg dfscv mmhjk xxddc yybgb zznbn ccubao uaitu acv GXCV ET GDG YH FG BCVB FJFH CBRE CBC GDG ET54 WRWR RWER WREW WRWER RWER SDG EW SF DSFSF fbbs ubao fhd dfg ewr dg df ewwr ewwr et ruyut utut dfg fgd gdfgt etg dfgt dfgd ert4 gd fgg wr 235 wer3 we vsdf sdf gdf ert xcv sdf rwer hfd dfg cvb rwf afb dfh jgh bmn lgh rty gfds cxv xcv xcs vdas fdf fgd cv sdf tert sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf shasha9178 shasha9178 shasha9178 shasha9178 shasha9178 liflif2 liflif2 liflif2 liflif2 liflif2 liblib3 liblib3 liblib3 liblib3 liblib3 zhazha444 zhazha444 zhazha444 zhazha444 zhazha444 dende5 dende denden denden2 denden21 fenfen9 fenf619 fen619 fenfe9 fe619 sdf sdf sdf sdf sdf zhazh90 zhazh0 zhaa50 zha90 zh590 zho zhoz zhozh zhozho zhozho2 lislis lls95 lili95 lils5 liss9 sdf0ty987 sdft876 sdft9876 sdf09876 sd0t9876 sdf0ty98 sdf0976 sdf0ty986 sdf0ty96 sdf0t76 sdf0876 df0ty98 sf0t876 sd0ty76 sdy76 sdf76 sdf0t76 sdf0ty9 sdf0ty98 sdf0ty987 sdf0ty98 sdf6676 sdf876 sd876 sd876 sdf6 sdf6 sdf9876 sdf0t sdf06 sdf0ty9776 sdf0ty9776 sdf0ty76 sdf8876 sdf0t sd6 sdf06 s688876 sd688 sdf86