bash脚本文件移除旧的超过15个月

Question

在bash脚本，如果我想删除比在目录15天旧文件，我可以运行：

find "$DIR" -type f -mtime +15 -exec rm {} \; 

有人可以帮我一个bash脚本删除目录中超过15个月的文件？

这与Bash中的ctime相同吗？

Answer 1

按照手册页：

-mtime n[smhdw] 
     If no units are specified, this primary evaluates to true if the difference between the file last modification time and the time find was started, rounded up to the next 
     full 24-hour period, is n 24-hour periods. 

     If units are specified, this primary evaluates to true if the difference between the file last modification time and the time find was started is exactly n units. Please 
     refer to the -atime primary description for information on supported time units. 

然后，在-atime：

-atime n[smhdw] 
     If no units are specified, this primary evaluates to true if the difference between the file last access time and the time find was started, rounded up to the next full 
     24-hour period, is n 24-hour periods. 

     If units are specified, this primary evaluates to true if the difference between the file last access time and the time find was started is exactly n units. Possible 
     time units are as follows: 

     s  second 
     m  minute (60 seconds) 
     h  hour (60 minutes) 
     d  day (24 hours) 
     w  week (7 days) 

     Any number of units may be combined in one -atime argument, for example, ``-atime -1h30m''. Units are probably only useful when used in conjunction with the + or - modi- 
     fier. 

因此，我们有几个星期。 15个月* 4周/月= 60周。

find $DIR -type f -mtime +60w -exec rm {} \; 

Answer 2

使用450（= 15 * 30）作为-mtime参数。

find $DIR -type f -mtime +450 -exec rm {} \; 

Answer 3

一个有趣的可能性：你可以touch时间戳15 months ago一个tmp文件，并与（否定）-newer标志find使用它：

a=$(mktemp) 
touch -d '15 months ago' -- "$a" 
find "$DIR" -type f \! -newer "$a" -exec rm {} + 
rm -- "$a" 

这当然，假定您touch和find具有这些功能。

如果有可能mktemp在您的目录$DIR的子目录中创建文件，它将变得非常混乱，因为在过程结束之前可以删除引用“$ a”的文件。在这种情况下，100％肯定的是，使用（否定）-samefile测试：

find "$DIR" -type f \! -newer "$a" \! -samefile "$a" -exec rm {} + 

当然你也可以使用find的-delete命令，如果您find支持它。这将给：

a=$(mktemp) 
touch -d '15 months ago' -- "$a" 
find "$DIR" -type f \! -newer "$a" \! -samefile "$a" -delete 
rm -- "$a" 

Answer 4

http://linux.die.net/man/8/tmpwatch正是为这个应用而设计的。通常与cron一起使用。