转自：http://www.cnblogs.com/sunyubo/archive/2011/10/17/2282047.html
1. shell判断文件,目录是否存在或者具有权限
2. #!/bin/sh 3. 4. myPath="/var/log/httpd/" 5. myFile="/var /log/httpd/access.log" 6. 7. # 这里的-x 参数判断$myPath是否存在并且是否具有可执行权限 8. if [ ! -x "$myPath"]; then 9. mkdir "$myPath" 10. fi 11. 12. # 这里的-d 参数判断$myPath是否存在 13. if [ ! -d "$myPath"]; then 14. mkdir "$myPath" 15. fi 16. 17. # 这里的-f参数判断$myFile是否存在 18. if [ ! -f "$myFile" ]; then 19. touch "$myFile" 20. fi 21. 22. # 其他参数还有-n,-n是判断一个变量是否是否有值 23. if [ ! -n "$myVar" ]; then 24. echo "$myVar is empty" 25. exit 0 26. fi 27. 28. # 两个变量判断是否相等 29. if [ "$var1" = "$var2" ]; then 30. echo '$var1 eq $var2' 31. else 32. echo '$var1 not eq $var2' 33. fi -f 和-e的区别 Conditional Logic on Files -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 or named 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 a terminal 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. 是用 -s 还是用 -f 这个区别是很大的！
