shell 脚本里启动多进程执行详解程序员

下面是shell脚本的部分代码，改代码段是并发 gpg 加密

echo "gpg start...`date` " 
#并发加密文件,缩短执行时间 
for FILE in `ls -1 /backup/base*.tgz` 
do 
  ( gpg -er postgres -o ${FILE}.gpg ${FILE} 
   )& 
done 
wait 
echo "gpg end...`date` "