Linux下好用的日志库,我使用過的Linux命令之tailf - 跟蹤日志文件/更好的tail -f版本...
用途說明
tailf命令幾乎等同於tail -f，嚴格說來應該與tail --follow=name更相似些。當文件改名之后它也能繼續跟蹤，特別適合於日志文件的跟蹤(follow the growth of a log file)。與tail -f不同的是，如果文件不增長，它不會去訪問磁盤文件(It is similar to tail -f but does not access the file when it is not growing.? This has the side effect of not updating the access? time for the file, so a filesystem flush does not occur periodically when no log activity is happening.)。tailf特別適合那些便攜機上跟蹤日志文件，因為它能省電，因為減少了磁盤訪問嘛(tailf? is extremely useful for monitoring log files on a laptop when logging is infrequent and the user desires that the hard disk spin down to conserve battery life.)。tailf命令不是個腳本，而是一個用C代碼編譯后的二進制執行文件，某些Linux安裝之后沒有這個命令，本文提供了怎么編譯安裝tailf命令的方法。
常用參數
格式：tailf logfile
動態跟蹤日志文件logfile，最初的時候打印文件的最后10行內容。
使用示例
示例一 使用tailf命令跟蹤日志
[root@web imx_server]#?tailf log/WEB.LOG
"seq": 5710,
"clientId": 1291343201649254,
"presenceStatus": "1"
} }})
16:09:21.324 DEBUG http-80-79 hyjc.cometd.CometdServlet - { "cid": 1291343201649002, "op": "recv", "ncc0": 175}
16:09:21.444 DEBUG http-80-32 hyjc.filter.AccessCounterFilter - uri=/imx/cometd/service
16:09:21.506 DEBUG http-80-79 hyjc.filter.AccessCounterFilter - uri=/imx/cometd/service
16:09:23.239 DEBUG http-80-45 hyjc.cometd.CometdServlet - { "cid": 1291343201649184, "op": "recv", "ncc0": 55}
16:09:23.327 DEBUG http-80-45 hyjc.filter.AccessCounterFilter - uri=/imx/cometd/service
16:09:24.288 DEBUG http-80-145 hyjc.cometd.CometdServlet - { "cid": 1291283017076175, "op": "recv", "ncc0": 82}
16:09:24.339 DEBUG http-80-81 hyjc.cometd.CometdServlet - { "cid": 1291283017076151, "op": "recv", "ncc0": 142}
16:09:24.360 DEBUG http-80-64 hyjc.cometd.CometdServlet - { "cid": 1291343201649090, "op": "recv", "ncc0": 40}
16:09:24.359 DEBUG http-80-143 hyjc.cometd.CometdServlet - { "cid": 1291283017076176, "op": "recv", "ncc0": 66}
16:09:24.878 DEBUG http-80-145 hyjc.filter.AccessCounterFilter - uri=/imx/cometd/service
16:09:24.892 DEBUG http-80-143 hyjc.filter.AccessCounterFilter - uri=/imx/cometd/service
16:09:24.896 DEBUG http-80-64 hyjc.filter.AccessCounterFilter - uri=/imx/cometd/service
16:09:24.906 DEBUG http-80-81 hyjc.filter.AccessCounterFilter - uri=/imx/cometd/service
16:09:25.095 DEBUG http-80-115 hyjc.filter.AccessCounterFilter - uri=/imx/cometd/service
16:09:25.095 DEBUG http-80-115 hyjc.cometd.CometdServlet - msgType IMX_ACTIVE_TEST msgBody {"clientId":1291343201649002,"presenceStatus":"1","seq":385}
16:09:25.095? INFO http-80-115 imx.client.ImxClient - Tx IMX_ACTIVE_TEST{seq=5711,client_id=1291343201649002,presence_status=1(presence_status_online),}
16:09:25.095 DEBUG http-80-115 hyjc.cometd.CometdServlet - { "cid": 1291343201649002, "op": "send", "sent": 0, "rc": 1, "msg": { "mt": "IMX_ACTIVE_TEST", "mb": {
"seq": 5711,
"clientId": 1291343201649002,
"presenceStatus": "1"
} }}
Ctrl+C
[root@web imx_server]#
示例二 編譯安裝tailf命令
有些Linux版本不帶tailf命令的。
[root@smsgw root]#?tailf
-bash: tailf: command not found
[root@smsgw root]#
到代碼搜索網站www.koders.com輸入tailf.c就可以搜索到源代碼
tailf.c結果頁面：http://www.koders.com/default.aspx?s=tailf.c&submit=Search&la=*&li=*
tailf.c源碼頁面：http://www.koders.com/c/fidB6EFAC156A7B4C4A46B38039C79B4AD34939EED0.aspx?s=tailf#L1
點左上角的download就可下載，也可直接下載本文附件tailf.zip。
[root@smsgw tailf]#?unzip tailf.zip
Archive:? tailf.zip
inflating: tailf.c
[root@smsgw tailf]#?ls
tailf.c? tailf.zip
[root@smsgw tailf]#?gcc -o /usr/bin/tailf tailf.c
tailf.c:34:17: nls.h: 沒有那個文件或目錄
tailf.c: In function `tailf':
tailf.c:53: warning: passing arg 2 of `fprintf' makes pointer from integer without a cast
tailf.c: In function `main':
tailf.c:88: `LC_ALL' undeclared (first use in this function)
tailf.c:88: (Each undeclared identifier is reported only once
tailf.c:88: for each function it appears in.)
tailf.c:89: `PACKAGE' undeclared (first use in this function)
tailf.c:89: `LOCALEDIR' undeclared (first use in this function)
tailf.c:93: warning: passing arg 2 of `fprintf' makes pointer from integer without a cast
tailf.c:105: warning: passing arg 2 of `fprintf' makes pointer from integer without a cast
[root@smsgw tailf]#
修改一下tailf.c的源代碼。
第34行附近：注釋掉頭文件，增加宏定義
//#include "nls.h"
#define _(s) s
第89行附近：把原來的代碼注釋掉
//setlocale(LC_ALL, "");
//bindtextdomain(PACKAGE, LOCALEDIR);
//textdomain(PACKAGE);
看了源代碼之后，你是不是發現其實Linux命令其實並不太神秘。
注：本文附件中的tailf.c已經修改成下面的樣子。
C代碼??
/*?tailf.c?--?tail?a?log?file?and?then?follow?it
*?Created:?Tue?Jan??9?15:49:21?1996?by?faith@acm.org
*?Copyright?1996,?2003?Rickard?E.?Faith?(faith@acm.org)
*
*?Permission?is?hereby?granted,?free?of?charge,?to?any?person?obtaining?a
*?copy?of?this?software?and?associated?documentation?files?(the?"Software"),
*?to?deal?in?the?Software?without?restriction,?including?without?limitation
*?the?rights?to?use,?copy,?modify,?merge,?publish,?distribute,?sublicense,
*?and/or?sell?copies?of?the?Software,?and?to?permit?persons?to?whom?the
*?Software?is?furnished?to?do?so,?subject?to?the?following?conditions:
*
*?The?above?copyright?notice?and?this?permission?notice?shall?be?included
*?in?all?copies?or?substantial?portions?of?the?Software.
*
*?THE?SOFTWARE?IS?PROVIDED?"AS?IS",?WITHOUT?WARRANTY?OF?ANY?KIND,?EXPRESS?OR
*?IMPLIED,?INCLUDING?BUT?NOT?LIMITED?TO?THE?WARRANTIES?OF?MERCHANTABILITY,
*?FITNESS?FOR?A?PARTICULAR?PURPOSE?AND?NONINFRINGEMENT.?IN?NO?EVENT?SHALL
*?THE?AUTHORS?OR?COPYRIGHT?HOLDERS?BE?LIABLE?FOR?ANY?CLAIM,?DAMAGES?OR
*?OTHER?LIABILITY,?WHETHER?IN?AN?ACTION?OF?CONTRACT,?TORT?OR?OTHERWISE,
*?ARISING?FROM,?OUT?OF?OR?IN?CONNECTION?WITH?THE?SOFTWARE?OR?THE?USE?OR
*?OTHER?DEALINGS?IN?THE?SOFTWARE.
*
*?less?-F?and?tail?-f?cause?a?disk?access?every?five?seconds.??This
*?program?avoids?this?problem?by?waiting?for?the?file?size?to?change.
*?Hence,?the?file?is?not?accessed,?and?the?access?time?does?not?need?to?be
*?flushed?back?to?disk.??This?is?sort?of?a?"stealth"?tail.
*/
#include?
#include?
#include?
#include?
#include?
//#include?"nls.h"
#define?_(s)?s
static?size_t?filesize(const?char?*filename)
{
struct?stat?sb;
if?(!stat(filename,?&sb))?return?sb.st_size;
return?0;
}
static?void?tailf(const?char?*filename,?int?lines)
{
char?**buffer;
int??head?=?0;
int??tail?=?0;
FILE?*str;
int??i;
if?(!(str?=?fopen(filename,?"r")))?{
fprintf(stderr,?_("Cannot?open?\"%s\"?for?read\n"),?filename);
perror("");
exit(1);
}
buffer?=?malloc(lines?*?sizeof(*buffer));
for?(i?=?0;?i?
while?(fgets(buffer[tail],?BUFSIZ,?str))?{
if?(++tail?>=?lines)?{
tail?=?0;
head?=?1;
}
}
if?(head)?{
for?(i?=?tail;?i?
for?(i?=?0;?i?
}?else?{
for?(i?=?head;?i?
}
fflush(stdout);
for?(i?=?0;?i?
free(buffer);
}
int?main(int?argc,?char?**argv)
{
char???????buffer[BUFSIZ];
size_t?????osize,?nsize;
FILE???????*str;
const?char?*filename;
int????????count;
//setlocale(LC_ALL,?"");
//bindtextdomain(PACKAGE,?LOCALEDIR);
//textdomain(PACKAGE);
if?(argc?!=?2)?{
fprintf(stderr,?_("Usage:?tailf?logfile\n"));
exit(1);
}
filename?=?argv[1];
tailf(filename,?10);
for?(osize?=?filesize(filename);;)?{
nsize?=?filesize(filename);
if?(nsize?!=?osize)?{
if?(!(str?=?fopen(filename,?"r")))?{
fprintf(stderr,?_("Cannot?open?\"%s\"?for?read\n"),?filename);
perror(argv[0]);
exit(1);
}
if?(!fseek(str,?osize,?SEEK_SET))
while?((count?=?fread(buffer,?1,?sizeof(buffer),?str))?>?0)
fwrite(buffer,?1,?count,?stdout);
fflush(stdout);
fclose(str);
osize?=?nsize;
}
usleep(250000);?????/*?250mS?*/
}
return?0;
}
[root@smsgw tailf]#?gcc -Wall -o /usr/bin/tailf tailf.c
[root@smsgw tailf]#?tailf
Usage: tailf logfile
[root@smsgw tailf]#
下載次數: 16
創作挑戰賽新人創作獎勵來咯，堅持創作打卡瓜分現金大獎總結
以上是生活随笔為你收集整理的Linux下好用的日志库,我使用過的Linux命令之tailf - 跟蹤日志文件/更好的tail -f版本...的全部內容，希望文章能夠幫你解決所遇到的問題。
- 上一篇： c# mysql 操作_c#对mysql
- 下一篇： tablednd保存 php,JQuer