for #!/bin/bash for i in 1 2 3 4 5 do echo "Welcome $i times" done for i in $( ls ); do echo item: $i done for i in `seq 1 10`; do echo $i done for i in {1..5} do echo "Welcome $i times" done for (( c=1; c<=5; c++ )) do echo "Welcome $c times..." done for i in {0..10..2} do echo "Welcome $i times" done for i in $(seq 1 2 20) do echo "Welcome $i times" done
infinite loops
#!/bin/bash for (( ; ; )) do echo "infinite loops [ hit CTRL+C to stop]" done
find file
#!/bin/bash for file in /etc/* do if [ "${file}" == "/etc/resolv.conf" ] then countNameservers=$(grep -c nameserver /etc/resolv.conf) echo "Total ${countNameservers} nameservers defined in ${file}" break fi done
backup file
#!/bin/bash FILES="$@" for f in $FILES do # if .bak backup file exists, read next file if [ -f ${f}.bak ] then echo "Skiping $f file..." continue # read next file and skip cp command fi # we are hear means no backup file exists, just use cp command to copy file /bin/cp $f $f.bak done
