如何通过 bash 脚本访问 .dev 文件

Question

下面是一个device.dev 文件，其中包含名为ads2 的特定应用程序的一些配置信息。

1 DEVICES {
2        GLOBAL-CONFIG {
3            framerate = "20000";
4            subframes = "0";
5            max_consec_timeouts = "10";
6            max_total_timeouts = "1000";
7            schedmode = "Standard";
8        }
9        IO-DEVICES {
10        }
11        COMPUTING-DEVICES {
12            RT_WORKSTATION x-NB-0144 = {
13                hostname = "x-x-0144";
14                ipaddress = "xxx.x.x.xx";
15                DISPLAYS {
16                    main = "FDT-C-VM-0094:0.0";
17                }
18                SCHEDPARAM {
19                    active = "0";
20                    framerate = "20000";
21                    subframes = "0";
22                    max_consec_timeouts = "10";
23                    max_total_timeouts = "1000";
24                }
25            }
27  
28            RT_HOST xxx-c-agx-vw-89 = { 
29                hostname = "xxxxx@xxxx-desktop";
30                ipaddress = "xx.xx.xx.xx";         
31                SCHEDPARAM {
32                    active = "0";
33                    framerate = "20000";
34                    subframes = "0";
35                    max_consec_timeouts = "10";
36                   max_total_timeouts = "1000";
37                }
38            }
39        }
40    }

我正在尝试编写一个接受 IP 地址输入的 bash 脚本，然后访问 device.dev 文件并将其传递给第 30 行中的变量 ipaddress。

那么是否可以通过 bash 脚本访问 devices.dev 文件？

提前致谢

Answer 1

使用 GNU awk 并只关注第二个条目：

awk -v ipadd="1.1.1.1" '/ipaddress/ { cnt++ } /ipaddress/ && cnt==2 { lne=gensub(/(^.*\")(.*)(\".*$)/,"\\1"ipadd"\\3",$0);print lne;next }1' devices.dev > devices.tmp && mv -f devices.tmp devices.dev

解释：

awk -v ipadd="1.1.1.1" '/ipaddress/ {                                          # Pass the ip address to change to as a variable ipadd to awk
            cnt++                                                              # Where there is ipaddress in the line, increment a cnt variable
         } 
/ipaddress/ && cnt==2 {                                                        # Where there is ipaddress in the line and cnt is 2, process
            lne=gensub(/(^.*\")(.*)(\".*$)/,"\\1"ipadd"\\3",$0);               # Set a variable lne to an entry that substitutes the existing IP address for the one passed in ipadd using awk's gensub function
            print lne;                                                         # Print the amendment
            next                                                               # Skip to the next line
         }1' devices.dev > devices.tmp && mv -f devices.tmp devices.dev        # Print all none amended lines and redirect the output to a temp file (devices.tmp) before over writing the devices.dev file with the temp file

Answer 2

假设你想在第 30 行完全替换 value，你可以在 device.dev 的同一目录中创建这个文件 sed.sh

#!/bin/bash
IP=$1
sed -i "30s/ipaddress.*/ipaddress = \"$IP\"/" device.dev

并执行

bash sed.sh 1.2.3.4

device.dev 在第 30 行将有 1.2.3.4