摘要：xargs 命令 用途 构造参数列表并运行命令。 语法 xargs [ -p ] [ -t ] [ -e [ eofstring ] ] [ -e eofstring ] [ -i [ replacestring ] ] [ -i replacestring ] [ -l [ number ] ] [ -l number ] [ -n number [ -x ] ] [ -s size ] [ c......
摘要：bash中对变量的操作 =============== bash内建参数 =========== bash中对变量的操作 =============== 1.条件变量替换: bash shell可以进行变量的条件替换,既只有某种条件发生时才进行替换,替换 条件放在{}中. (1) $ 当变量未定义或者值为空时,返回值为word的内容,否则返回变量的值. (2) $ 与前者类似,只是若变量未定义或者......
Bash 内建命令 readread [-ers] [-u fd] [-t timeout] [-a aname] [-p prompt] [-n nchars] [-d delim] [name ...] one line is read from the standard input, or from the file descriptor fd supplied as an argument to the -u option, and the first word is assigned to the first name, the second word to the second name, and so on, with leftover words and their intervening separators assigned to the last name. if there are fewer words read from the input stream than names, the remaining names are assigned empty values. the characters in ifs are used to split the line into words. the backslash character (\) may be used to remove any special meaning for the next character read and for line continuation. options, if supplied, have the following meanings: 【程序编程相关:
《学VC、编游戏》重点算法解疑·快一点
】 【推荐阅读:
Windows的消息机制与消息重定向技术】 -a aname 【扩展信息:
《学VC、编游戏》重点算法解疑·狩猎谋生】 the words are assigned to sequential indices of the array variable aname, starting at 0. aname is unset before any new values are assigned. other name arguments are ignored. -d delim ...
下一页 摘要：dd 是 linux/unix 下的一个非常有用的命令，作用是用指定大小的块拷贝一个文件，并在拷贝的同时进行指定的转换。
dd 的主要选项：
指定数字的地方若以下列字符结尾乘以相应的数字:
b=512, c=1, k=1024, w=2, xm=number m
if=file
输入文件名，缺省为标准输入。
of=file
输出文件名，缺省为标准输出。
ibs=byte......
