转载自：
http://www.linuxdiyf.com/linux/21351.html
Consolas 字体用来写代码真的是非常舒服，可惜 ubuntu 系统中默认并没有这个字体，我们需要自己下载安装，本文就介绍了如何自己手动下载并安装如上字体。先来看一下vim下使用 Consolas 字体的效果图吧。
【字体下载】
YaHeiConsolas.tar：http://www.mycode.net.cn/wp-content/uploads/2015/07/Ya[……]
默认zlib的API，是只压缩数据，无法处理gzip文件的，因为无法解析头文件信息。
备注：初始化参数那个，也可以这么搞 MAX_WBITS + 16，读了Python的源码用的是这种方法。
以下转载自：http://www.lemoda.net/c/zlib-open-read/
压缩：
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#include <stdio.h> #include <zlib.h> #include <stdlib.h> #include <string.h> /* CHUNK is the size of the memory chunk used by the zlib routines. */ #define CHUNK 0x4000 /* The following macro calls a zlib routine and checks the return value. If the return value ("status") is not OK, it prints an error message and exits the program. Zlib's error statuses are all less than zero. */ #define CALL_ZLIB(x) { \ int status; \ status = x; \ if (status < 0) { \ fprintf (stderr, \ "%s:%d: %s returned a bad status of %d.\n", \ __FILE__, __LINE__, #x, status); \ exit (EXIT_FAILURE); \ } \ } /* These are parameters to deflateInit2. See http://zlib.net/manual.html for the exact meanings. */ #define windowBits 15 #define GZIP_ENCODING 16 static void strm_init (z_stream * strm) { strm->zalloc = Z_NULL; strm->zfree = Z_NULL; strm->opaque = Z_NULL; CALL_ZLIB (deflateInit2 (strm, Z_DEFAULT_COMPRESSION, Z_DEFLATED, windowBits | GZIP_ENCODING, 8, Z_DEFAULT_STRATEGY)); } /* Example text to print out. */ static const char * message = "Shall I compare thee to a summer's day?\n" "Thou art more lovely and more temperate:\n" "Rough winds do shake the darling buds of May,\n" "And summer's lease hath all too short a date;\n" ; int main () { unsigned char out[CHUNK]; z_stream strm; strm_init (& strm); strm.next_in = (unsigned char *) message; strm.avail_in = strlen (message); do { int have; strm.avail_out = CHUNK; strm.next_out = out; CALL_ZLIB (deflate (& strm, Z_FINISH)); have = CHUNK - strm.avail_out; fwrite (out, sizeof (char), have, stdout); } while (strm.avail_out == 0); deflateEnd (& strm); return 0; } |
解压缩：
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#include <stdio.h> /* For "exit". */ #include <stdlib.h> /* For "strerror". */ #include <string.h> /* For "errno". */ #include <errno.h> #include <zlib.h> /* CHUNK is the size of the memory chunk used by the zlib routines. */ #define CHUNK 0x4000 /* The following macro calls a zlib routine and checks the return value. If the return value ("status") is not OK, it prints an error message and exits the program. Zlib's error statuses are all less than zero. */ #define CALL_ZLIB(x) { \ int status; \ status = x; \ if (status < 0) { \ fprintf (stderr, \ "%s:%d: %s returned a bad status of %d.\n", \ __FILE__, __LINE__, #x, status); \ exit (EXIT_FAILURE); \ } \ } /* if "test" is true, print an error message and halt execution. */ #define FAIL(test,message) { \ if (test) { \ inflateEnd (& strm); \ fprintf (stderr, "%s:%d: " message \ " file '%s' failed: %s\n", \ __FILE__, __LINE__, file_name, \ strerror (errno)); \ exit (EXIT_FAILURE); \ } \ } /* These are parameters to inflateInit2. See http://zlib.net/manual.html for the exact meanings. */ #define windowBits 15 #define ENABLE_ZLIB_GZIP 32 int main () { const char * file_name = "test.gz"; FILE * file; z_stream strm = {0}; unsigned char in[CHUNK]; unsigned char out[CHUNK]; strm.zalloc = Z_NULL; strm.zfree = Z_NULL; strm.opaque = Z_NULL; strm.next_in = in; strm.avail_in = 0; CALL_ZLIB (inflateInit2 (& strm, windowBits | ENABLE_ZLIB_GZIP)); /* Open the file. */ file = fopen (file_name, "rb"); FAIL (! file, "open"); while (1) { int bytes_read; bytes_read = fread (in, sizeof (char), sizeof (in), file); FAIL (ferror (file), "read"); strm.avail_in = bytes_read; do { unsigned have; strm.avail_out = CHUNK; strm.next_out = out; CALL_ZLIB (inflate (& strm, Z_NO_FLUSH)); have = CHUNK - strm.avail_out; fwrite (out, sizeof (unsigned char), have, stdout); } while (strm.avail_out == 0); if (feof (file)) { inflateEnd (& strm); break; } } FAIL (fclose (file), "close"); return 0; } |
命令为：
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sudo netstat -lnp |
截取某一行，如下所示：
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tcp 0 0 0.0.0.0:3306 0.0.0.0:* LISTEN 1137/mysqld |
其中，3306就是本地server打开的端口号，1137是进程pid。
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# 分割符为, file是文件 paste -d, -s file # 使用管道，分割符为空格 cat file | paste -d " " -s - |
如何在Linux中将文件或者stdin的多行合并为1行，如上所示。
有的时候，我们明明在/etc/cron.d下创建了cron文件，却没法执行，此时可以如下排查：
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sudo tail -f /var/log/cron |
这个是分钟级别的cron执行日志，检查下你的脚本是否执行有错误，或者权限问题。
例如：
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Nov 27 11:55:01 xxxxx crond[3957]: (*system*) WRONG FILE OWNER (/etc/cron.d/xxxx-cron) |
可以看到，是cron文件必须为root。