Linux 命令大全
Linux fold命令用于限制文件列宽。
为了解决多读取的eof字符(在文件中不可见)linux命令，我们用一个小小的逻辑算法来避免eof字符带来的困惑，如打印读取的文件内容时不将读取到的eof字符输出，或避免在读取到eof字符（读取此字符不成功）后无判断文件是否结束的操作而又将上一次读取到的数据输出。软件功能：1.可以定位模拟操作任何窗口包括最小化和隐藏的窗口2.支持代理换ip和拨号换ip3.自动打码（图片验证码自动识别 ）4.运行任意程序文件5.强大的标准式和正则表达式文件提取功能6.自动鼠标点击操作7.支持固定时间和随机时间停顿8.随机字符自动填写9.键盘按键模拟（包括单键和系统组合键）10.向指定区域快速发送文本内容11.批量进行软件登录操作12.快速文本存在判断13.网页链接提取和元素操作（网页文本输入和按钮点击）14.文本拷贝（自动拷贝文本到剪切板）15.指定窗体自动关闭16.结束进程17.自动打开网页18.清除internet临时文件更新日志：1、修正了内部操作中执行脚本列表的bug2、修正了读取文本列表5数据失败的bug3、添加了网页操作中发送文本使用变量“自动编号”（比如有些input标签没有name或者id参数又有其他很多相同的input标签程序无法定位。在读取文件时，不仅要注意行结束符号“\n”，程序也需要一种标准的方式来识别何时到达文件的末尾，这个标准通常成为eof（end of file）字符。
fold [-bs][-w<每列行数>][--help][--version][文件...]
参数：
将一个名为testfile 的文件的行折叠成宽度为30linux命令，可使用如下命令：
fold -w 30 testfile
为了对比，先将testfile文件输出如下：
$ cat testfile #查看testfile 中的内容 Linux networks are becoming more and more common, but security is often an overlooked issue. Unfortunately, in today’s environment all networks are potential hacker targets, from top-secret military research networks to small home LANs. Linux Network Security focuses on securing Linux in a networked environment, where the security of the entire network needs to be considered rather than just isolated machines. It uses a mix of theory and practical techniques to teach administrators how to install and use security applications, as well as how the applications work and why they are necessary.
然后使用fold命令折叠显示：
$ fold -w 30 testfile #行折叠成宽度为30，显示testfile 文件 Linux networks are becoming mo re and more common, but securi ty is often an overlooked issu e. Unfortunately, in today’s environment all networks are potential hacker targets, from top-secret military research networks to small home LANs. Linux Network Security focuses on securing Linux in a networ ked environment, where the sec urity of the entire network ne eds to be considered rather th an just isolated machines. It uses a mix of theory and pract ical techniques to teach admin istrators how to install and u se security applications, as w ell as how the applications wo rk and why they are necessary
Linux 命令大全
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