c语言读取每一行，再将符合条件的写入另一个文件中。_c语言查找文件中每行是否包含指定字符串并将此行写入新文件-优快云博客

本文链接：https://blog.youkuaiyun.com/lilylvchen/article/details/49923875

这篇博客讲述了作者如何使用C语言读取包含特定格式的文件，当行首字符为数字时，将这些行写入新的文件中。文章介绍了fopen、fclose、feof、fgets、isdigit和fputs等函数的用法，并分享了完整代码，以及在处理文件时的注意事项。

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已经很久没有碰过c语言了，可能很多同学都觉得so easy。重新拾起来还是有点害怕&激动。

拾起来的时候犯了很多新手会返的错误，对不起大学老师了。╮(￣▽￣")╭

写这玩意的原因是开发扔了一份gc.log给我，打出来的是详细信息，

比如：

<span style="font-family:Comic Sans MS;">2015-10-29T20:16:13.757+0800: 4.237: [GC [PSYoungGen: 1280000K->25644K(1493312K)] 1280000K->25644K(4906688K), 0.0096300 secs] [Times: user=0.05 sys=0.04, real=0.01 secs] 
Total time for which application threads were stopped: 0.0098530 seconds
Application time: 0.0020110 seconds
Total time for which application threads were stopped: 0.0001470 seconds
Application time: 0.0000300 seconds
Total time for which application threads were stopped: 0.0002440 seconds
Application time: 0.0000300 seconds
Total time for which application threads were stopped: 0.0001120 seconds
Application time: 0.0000540 seconds
Total time for which application threads were stopped: 0.0001960 seconds
Application time: 0.0000270 seconds
Total time for which application threads were stopped: 0.0000570 seconds
Application time: 0.0000420 seconds
Total time for which application threads were stopped: 0.0001250 seconds
Application time: 0.0000290 seconds
Total time for which application threads were stopped: 0.0001090 seconds
Application time: 0.0000270 seconds</span>

但是我可能不太需要具体的线程停止的时间，比如：

<span style="font-family:Comic Sans MS;">2015-10-31T23:03:46.204+0800: 182856.684: [GC [PSYoungGen: 1355299K->309811K(1237120K)] 4059775K->3237002K(4650496K), 0.0469180 secs] [Times: user=0.46 sys=0.00, real=0.04 secs] 
2015-10-31T23:05:42.228+0800: 182972.708: [GC [PSYoungGen: 1237107K->260369K(1556288K)] 4164298K->33