linux系统shell脚本中文件判断的几个实例

在写shell脚本的时候经常会用到if判断，下面是可能会经常使用的几个实例。包括判断目录是否存在，文件是否存在、变量是否相当等。
#!/bin/shmypath=\/var/log/httpd/\myfile=\/var /log/httpd/access.log\# 这里的-x 参数判断$mypath是否存在并且是否具有可执行权限if [ ! -x \$mypath\]; then ?mkdir \$mypath\fi# 这里的-d 参数判断$mypath是否存在if [ ! -d \$mypath\]; then ?mkdir \$mypath\fi# 这里的-f参数判断$myfile是否存在if [ ! -f \$myfile\ ]; then ?touch \$myfile\fi# 其他参数还有-n,-n是判断一个变量是否是否有值if [ ! -n \$myvar\ ]; then ?echo \$myvar is empty\ ?exit 0fi# 两个变量判断是否相等if [ \$var1\ = \$var2\ ]; then ?echo \'$var1 eq $var2\'else ?echo \'$var1 not eq $var2\'fi参数：
-a file exists.-b file exists and is a block special file.-c file exists and is a character special file.-d file exists and is a directory.-e file exists (just the same as -a).-f file exists and is a regular file.-g file exists and has its setgid(2) bit set.-g file exists and has the same group id as this process.-k file exists and has its sticky bit set.-l file exists and is a symbolic link.-n string length is not zero.-o named option is set on.-o file exists and is owned by the user id of this process.-p file exists and is a first in, first out (fifo) special file ornamed pipe.-r file exists and is readable by the current process.-s file exists and has a size greater than zero.-s file exists and is a socket.-t file descriptor number fildes is open and associated with aterminal device.-u file exists and has its setuid(2) bit set.-w file exists and is writable by the current process.-x file exists and is executable by the current process.-z string length is zero.


我这边因为时间问题需要先准备备案资料
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