Use AWK to separate and intercept strings

Use $0 to split the current string. for example, catnum.2012032911 | awk & amp; #39; {print $2} & amp; #39; | awk & amp; #39; {split ($0, B, & quot ;. & quot;); printb [2]} & amp; #39; | cut-c3-get the second column, for example, the second column is com. sb3456.y
Use $0 to split the current string. for example, cat num.2012032911 | awk '{print $2}' | awk '{split ($0, B ,". "); print B [2]} '| cut-c 3-get the second column, for example, the second column is com. sb3456.you, then obtain sb3456 from the current split string, and finally extract the sb3456 string from 3rd characters to the final result of 456 B = "c, d, e, f, g "echo | awk '{split ("' $ {B} '", array ,","); print array [1]} 'c echo $ B | cut-d ","-f2 d -www.2cto.com-where-d represents what is used for segmentation, -f2 indicates that 2nd results are required. another common parameter is-c, use-cx-y this means to get the echo "abcdefg" from the x to the y string | cut-c3-6 output is def formatted column-t but it seems to be mixed with tabs and spaces the condition cannot be processed string =/home/bozo/daily-journal.txt to intercept the specified string -www.2cto.com-echo | awk '{print substr ("' $ {string }'", 2, 4)} '// Obtain the length of the 4 characters starting from 2nd characters. The result is: home calculates the string length echo | awk' {print length ("'$ {string }'")} '// The result is: 29 string case-insensitive conversion echo | awk' {print toupper ("test"), tolower ("TEST")} '. The result is: MyEyeOfJava, author of TEST.