請問如何打印linux文件系統(tǒng)應(yīng)用程序中printf或者echo的時間戳

xrqun

我知道通過kernel的CONFIG_PRINTK_TIME來打印內(nèi)核運行printk的時間。
但是我想把文件系統(tǒng)中運行printf或者echo的時間戳也打印出來，和下面一樣。
不知道kernel或者文件系統(tǒng)中要添加什么？
[0.356417 0.356417] [ 0.046637] _regulator_get: get() with no identifier
[0.958425 0.602008] starting pid 21, tty '': '/unit_tests/mxc_v4l2_overlay.out -iw 640 -ih 480 -it 0 -il 0 -ow 1024 -oh 768 -ot 0 -ol 0 -r 0 -t -^@
[0.969609 0.011184] starting pid 22, tty '': '/etc/rc.d/rcS'
[0.973368 0.003759] g_display_width = 1024, g_display_height = 768
[0.977540 0.004172] g_display_top = 0, g_display_left = 0
[0.980927 0.003387] starting pid 23, tty '': '/sbin/getty -L ttymxc0 115200 vt100 '
[1.048454 0.067527] Mounting /proc and /sys
[1.089526 0.041072] Setting the hostname to freescale
[1.116635 0.027109] Mounting filesystems
[1.527320 0.410685] sensor chip is ov5640_mipi_camera
[1.530627 0.003307] sensor frame size is 640x480
[1.533482 0.002855] sensor frame format is UYVY
[1.640221 0.106739] frame_rate is 30
[1.642249 0.002028]
[1.642270 0.000021] frame buffer width 0, height 0, bytesperline 0
[1.989728 0.347458]
[1.990761 0.001033] arm-none-linux-gnueabi-gcc (Freescale MAD -- Linaro 2011.07 -- Built at 2011/08/10 09:20) 4.6.2 20110630 (prerelease)
[2.001161 0.010400] root filesystem built on Tue, 11 Sep 2012 11:43:24 +0800
[2.006249 0.005088] Freescale Semiconductor, Inc.
[2.009394 0.003145]
[2.009531 0.000137] freescale login:

MMMIX

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    把對應(yīng)的函數(shù)/命令修改或覆蓋了即可:
1. printf(3) 來自 libc;
2. printf(1) 是系統(tǒng)命令;
3. echo 是系統(tǒng)命令或 shell 內(nèi)置命令.