awk命令详解

 free -h|awk 'NR==2'
  396  free -h|awk 'NR==3'
  397  free -h|awk 'NR==2{print $NF}'
  398  free -h|awk 'NR==2{print $NF,$2}'
  399  free -h|awk 'NR==2{print $NF/$2}'
  400  free -h|awk 'NR==2{print $NF/$2*100}'
  401  free -h|awk 'NR==2{print int($NF/$2*100)}'
awk '$3~/^41/{print $1,$2,$3}' awk_test.txt 
  414  awk '$3~/1$|5$/{print $1$2}' awk_test.txt 
  415  awk '$3~/1$|5$/{print $1,$2}' awk_test.txt 
  416  awk '$3~/1$|5$/{print $1,$2}' awk_test.txt -n
  417  awk '$3~/1$|5$/{print $1,$2}' awk_test.txt|column -n
  418  awk '$3~/1$|5$/{print $1,$2}' awk_test.txt|column -t
  419  awk '$3~/[15]$/{print $1,$2}' awk_test.txt|column -t
  420  awk '$3~/(1|5)$/{print $1,$2}' awk_test.txt|column -t
  421  !
  422  cat awk_test.txt 
  423  awk '$2~/Xiaoyu/{gsub(/:/,"$",$NF),print $NF}' awk_test.txt 
  424  awk '$2~/Xiaoyu/{gsub(/:/,"$",$NF);print $NF}' awk_test.txt 
  425  history
  426  vim awk_test.txt 
  427  cat awk_test.txt 
  428  awk '/^#|^$/' awk_test.txt 
  429  awk '/!^#|^$/' awk_test.txt 
  430  awk '!/^#|^$/' awk_test.txt 
  431  awk '$0~/^#|^$/' awk_test.txt 
  432  awk '$0!~/^#|^$/' awk_test.txt 
  433  iP a
  434  ip a
  435  ip a s
  436  ip a s eth0
  437  ip -n
  438  ip --h
  439  ip a s --h
  440  man ip
  441  ip a sh
  442  ip a sh eth0
  443  ip a sh eth0|awk -F "[/]{print $2}"
  444  ip a sh eth0
  445  ip a sh eth0|awk -F "/" 'NR==2'
  446  ip a sh eth0|awk -F "/" 'NR==3'
  447  ip a sh eth0|awk -F "/" 'NR==3{print $2}'
  448  ip a sh eth0|awk -F "[ /]+" 'NR==3{print $2}'
  449  ip a sh eth0|awk -F "[ /]+" 'NR==3{print $3}'
  450  ip a sh eth0|awk -F "[ /]+" 'NR==3{print $1}'
  451  ip a sh eth0|awk -F "[ /]+" 'NR==3{print $3}'
  452  hostname -i
  453  awk 'BEGIN{print "姓","名","QQ号","捐款记录"}'
  454  awk 'BEGIN{print "姓","名","QQ号","捐款记录"}{print $0}' awk_test.txt 
  455  awk 'BEGIN{print "姓","名","QQ号","捐款记录"}{print $0}' awk_test.txt |coulmn -t
  456  awk 'BEGIN{print "姓","名","QQ号","捐款记录"}{print $0}' awk_test.txt |column -t
  457  awk 'BEGIN{print "姓","名","QQ号","捐款记录"}' awk_test.txt |column -t
  458  awk 'BEGIN{print "姓","名","QQ号","捐款记录"}{print $0}' awk_test.txt |column -t
  459  awk 'BEGIN{print 1+1}'
  460  awk 'BEGIN{print 1-9}'
  461  awk 'BEGIN{print 1*9}'
  462  awk 'BEGIN{print 1/9}'
  463  echo $((1+9))
  464  echo $((1/9))
  465  cat awk_test.txt 
  466  awk 'BEGIN{FS=":"}{print $2}END{print "操作结束"}' awk_test.txt 
  467  awk -vqhy=123 '{print qhy}' awk_test.txt 
  468  grep '^$' /etc/services 
  469  grep '^$' /etc/services -c
  470  awk '/^$/{i=i+1;print i}' /etc/services 
  471  awk '/^$/{i++;print i}' /etc/services 
  472  awk '/^$/{i++}END{print i}' /etc/services 
  473  cat /etc/passwd
  474  awk '$NF~/bash/' /etc/passwd
  475  awk '$NF~/bash/{i=i+1}END{print i}' /etc/passwd
  476  awk '$NF!~/bash/{i=i+1}END{print i}' /etc/passwd
  477  awk '$NF!~/bash/' /etc/passwd
  478  awk '$NF!~/bash/{i=i+1}END{print i}' /etc/passwd
  479  seq 10
  480  awk '{sum=sum+$n,print sum}'
  481  awk '{sum=sum+$n;print sum}'
  482  seq 10|awk '{sum=sum+$n;print sum}'
  483  cat awk_test.txt 
  484  awk -F ":" '{print $2,$NF}' awk_test.txt 
  485  awk -F ":" '{print $2,$NF}' awk_test.txt |awk '{sum=sum+$n;print $n}'
  486  awk -F ":" '{print $2,$NF}' awk_test.txt |awk '$1~{sum=sum+$n;print $n}'
  487  awk -F ":" '{print $2,$NF}' awk_test.txt |awk '$1~{sum=sum+$n;print}'
  488  awk -F ":" '{print $2,$NF}' awk_test.txt |awk '{sum=sum+$n}'
  489  awk -F ":" '{print $2,$NF}' awk_test.txt |awk '{sum=sum+$n;print $0}'
  490  seq 10|awk '{sum=sum+$1;print sum}'
  491  awk -F ":" '{print $2,$NF}' awk_test.txt |awk '{sum1=sum1+$1;sum2=sum2+$2;print sum1,sum2}'
  492  vim awk_test.txt 
  493  awk -F ":" '{print $2,$NF}' awk_test.txt |awk '{sum1=sum1+$1;sum2=sum2+$2;print sum1,sum2}'
    496  awk -F ":" 'BEGIN{print "第一次捐款总额","第二次捐款总额"}{print $2,$NF}' awk_test.txt |awk '{sum1=sum1+$1;sum2=sum2+$2;print sum1,sum2}'
  497  awk -F ":" '{print $2,$NF}' awk_test.txt |awk 'BEGIN{print "第一次捐款总额","第二次捐款总额"}{sum1=sum1+$1;sum2=sum2+$2;print sum1,sum2}'
  498  awk -F ":" '{print $2,$NF}' awk_test.txt |awk 'BEGIN{print "第一次捐款总额","第二次捐款总额"}{sum1=sum1+$1;sum2=sum2+$2;print sum1,sum2}'|column -t