Java™ Application Development on Linux - Dator

1.3 Basic Linux Concepts and Commands21Table 1.3 Some find predicatesOption-type d-type f-mtime -5-atime -5-newer myEx.class-size +24kExplanationIs true if the file is a directory.Is true if the file is a plain file (e.g., not a directory).Is true if the file is less than five days old, that is, has beenmodified within the last five days. A +5 would mean older thanfive days and a 5 with no sign means exactly five days.Is true if the file was accessed within the last five days. The +and - mean greater and less than the specified time, as in theprevious example.Is true if the file is newer than the file myEx.class.Is true if the file is greater than 24K. The suffix c would meanbytes or characters (since b stands for 512-byte blocks in thiscontext). The + and - mean greater and less than the specifiedsize, as in the other examples.$ find . -name '*.java' -mtime +90 -atime +30 -print./MyExample.java./old/sample/MyPrev.java$This command printed out the names of two files that end with .java foundbeneath the current directory. These files hadn’t been modified in the last90 days nor accessed within the last 30 days. The next thing you might wantto do is to run this command again adding something at the end to removethese old files.$ find . -name '*.java' -mtime +90 -atime +30 -print -exec rm '{}' \;./MyExample.java./old/sample/MyPrev.java$1.3.10 The Shell RevisitedMost Linux shells—the command interpreters—can be considered programminglanguages in their own right. That is, they have variables and controlstructures—if statements, for loops, and so on. While the syntax can be subtlydifferent between shells, the basic constructs are all there.