I am stuck with this homework, need to find most common commands in a text link.

In Linux, text processing and text analysis are essential. The following file contains the history of the commands of one of IT Slovenia’s system administrators. https://raw.githubusercontent.com/nuwanarti/Assignment1/main/data1 Please find the top three commands which are frequently shown in the file and save the result in ~/result.txt Tasks:

1. Process the text data.
2. Write the result to ~/result.txt
3. Ensure that results include the number of times and commands, such as "100 ls".

CodePudding user response：

Assumptions:

• OP is only interested in the initial command in any pipelined commands (eg, ps -ef | grep rabbitmq leads to ps being counted once, and grep is ignored)
• OP has access to GNU awk (for the PROCINFO["sorted_in"] option)
• the history (from that github link) is stored in file history.dat

One awk solution:

awk '
    { counts[$2]   }
END { PROCINFO["sorted_in"]="@val_num_desc"
      for (i in counts) {
           print counts[i],i
          if (  pass >= 3) 
             break
      }
    }
' history.dat

This generates:

199 tail
150 openstack
114 systemctl

CodePudding user response：

You can use history combined with awk, filter the results with uniq to get rid of the duplicates, then head -3 to get the top 3 results and finally redirect the output to ~/result.txt:

history | awk '{print $2}' | awk 'BEGIN {FS="|"} {print $1}' \
| sort | uniq -c | sort -rn | head -3 > ~/result.txt

Of course you need to switch from history to cat data1.txt if you are reading the results from a file.