linux从frame buffer中将qt界面拷贝出来放到u盘的操作方法

使用的是gsnap工具，源码可以在百度上搜,以Imx6为例的使用方法

root@imx6qsabresd:~#
root@imx6qsabresd:~#
root@imx6qsabresd:~# df
Filesystem     1K-blocks     Used Available Use% Mounted on
/dev/root         289293   197510     76423  73% /
devtmpfs          371004        0    371004   0% /dev
tmpfs             502220      200    502020   1% /run
tmpfs             502220        0    502220   0% /var/volatile
/dev/mmcblk1p1     45488      240     42688   1% /usr/cm/userconfig
/dev/mmcblk1p2     45488       44     42884   1% /usr/cm/dbBackup
/dev/mmcblk1p3   7111724    63728   6680076   1% /usr/cm/patdata
/dev/sda1       60401152 12102464  48298688  21% /var/volatile/tmp/udisk_sda1
root@imx6qsabresd:~# cd /var/volatile/tmp/udisk_sda1
root@imx6qsabresd:/var/volatile/tmp/udisk_sda1# ls
&EV                   SOFTUPDATE                 case_history1009
ComenProcessorExport  SOFTUPDATE-2000light       case_history1012
Export                System Volume Information  gnasp_tool.tar.gz
MyFile                case_backup                old
root@imx6qsabresd:/var/volatile/tmp/udisk_sda1# sync
root@imx6qsabresd:/var/volatile/tmp/udisk_sda1#
root@imx6qsabresd:/var/volatile/tmp/udisk_sda1#
root@imx6qsabresd:/var/volatile/tmp/udisk_sda1# cd /usr/cm/patdata
root@imx6qsabresd:/usr/cm/patdata# ls
AutoTestFile  gnasp_tool.tar.gz  systemLog
def_Autotest  lost+found         updateLog.txt
root@imx6qsabresd:/usr/cm/patdata# tar -xzvf ./gnasp_tool.tar.gz
gnasp_tool/
gnasp_tool/libjpeg.so.8.4.0
gnasp_tool/gnasp
gnasp_tool/libjpeg.so.8
gnasp_tool/libjpeg.so
root@imx6qsabresd:/usr/cm/patdata# ls
AutoTestFile  gnasp_tool         lost+found  updateLog.txt
def_Autotest  gnasp_tool.tar.gz  systemLog
root@imx6qsabresd:/usr/cm/patdata# cd ./gnasp_tool
root@imx6qsabresd:/usr/cm/patdata/gnasp_tool# ls
gnasp  libjpeg.so  libjpeg.so.8  libjpeg.so.8.4.0
root@imx6qsabresd:/usr/cm/patdata/gnasp_tool# ./gnasp

Usage: ./gnasp [jpeg|png file] [framebuffer dev]
Example: ./gnasp fb.jpg /dev/fb0
-----------------------------------------
Powered by broncho(www.broncho.cn)

root@imx6qsabresd:/usr/cm/patdata/gnasp_tool# ls
gnasp  libjpeg.so  libjpeg.so.8  libjpeg.so.8.4.0
root@imx6qsabresd:/usr/cm/patdata/gnasp_tool# ./gnasp 1.jpg

Usage: ./gnasp [jpeg|png file] [framebuffer dev]
Example: ./gnasp fb.jpg /dev/fb0
-----------------------------------------
Powered by broncho(www.broncho.cn)

root@imx6qsabresd:/usr/cm/patdata/gnasp_tool# ./gnasp 1.jpg /fb0
can't open /fb0
root@imx6qsabresd:/usr/cm/patdata/gnasp_tool# ls /dev
audio            loop0            network_throughput  stdin   tty31  tty57
audio1           loop1            null                stdout  tty32  tty58
autofs           loop2            pps0                tty     tty33  tty59
block            loop3            ptmx                tty0    tty34  tty6
bus              loop4            ptp0                tty1    tty35  tty60
char             loop5            pts                 tty10   tty36  tty61
console          loop6            ram0                tty11   tty37  tty62
cpu_dma_latency  loop7            ram1                tty12   tty38  tty63
disk             mem              ram10               tty13   tty39  tty7
dri              mixer            ram11               tty14   tty4   tty8
dsp              mixer1           ram12               tty15   tty40  tty9
dsp1             mmcblk1          ram13               tty16   tty41  ttymxc0
egalax_i2c       mmcblk1boot0     ram14               tty17   tty42  ttymxc1
fb0              mmcblk1boot1     ram15               tty18   tty43  ttymxc2
fb1              mmcblk1p1        ram2                tty19   tty44  ttymxc3
fb2              mmcblk1p2        ram3                tty2    tty45  ttymxc4
fd               mmcblk1p3        ram4                tty20   tty46  ubi_ctrl
full             mmcblk1rpmb      ram5                tty21   tty47  urandom
fuse             mmcblk3          ram6                tty22   tty48  vcs
galcore          mmcblk3boot0     ram7                tty23   tty49  vcs1
hwrng            mmcblk3boot1     ram8                tty24   tty5   vcsa
i2c-0            mmcblk3p1        ram9                tty25   tty50  vcsa1
i2c-1            mmcblk3rpmb      random              tty26   tty51  zero
i2c-2            mxc_asrc         sda                 tty27   tty52
initctl          mxc_hdmi         sda1                tty28   tty53
input            mxc_ipu          shm                 tty29   tty54
kmsg             mxc_vpu          snd                 tty3    tty55
loop-control     network_latency  stderr              tty30   tty56
root@imx6qsabresd:/usr/cm/patdata/gnasp_tool# ./gnasp 1.jpg /dev/fb0
---------------framebuffer---------------
/dev/fb0:
  width :     1280
  height:      720
  bpp   :        4
  r(16,  8)
  g( 8,  8)
  b( 0,  8)
-----------------------------------------
root@imx6qsabresd:/usr/cm/patdata/gnasp_tool# ls
1.jpg  gnasp  libjpeg.so  libjpeg.so.8  libjpeg.so.8.4.0
root@imx6qsabresd:/usr/cm/patdata/gnasp_tool# sync
root@imx6qsabresd:/usr/cm/patdata/gnasp_tool# df
Filesystem     1K-blocks     Used Available Use% Mounted on
/dev/root         289293   197510     76423  73% /
devtmpfs          371004        0    371004   0% /dev
tmpfs             502220      200    502020   1% /run
tmpfs             502220        0    502220   0% /var/volatile
/dev/mmcblk1p1     45488      240     42688   1% /usr/cm/userconfig
/dev/mmcblk1p2     45488       44     42884   1% /usr/cm/dbBackup
/dev/mmcblk1p3   7111724    64176   6679628   1% /usr/cm/patdata
/dev/sda1       60401152 12102464  48298688  21% /var/volatile/tmp/udisk_sda1
k_sda1/x6qsabresd:/usr/cm/patdata/gnasp_tool# cp ./1.jpg /var/volatile/tmp//udisk
root@imx6qsabresd:/usr/cm/patdata/gnasp_tool# cd /var/volatile/tmp/udisk_sda1
root@imx6qsabresd:/var/volatile/tmp/udisk_sda1# ls
&EV                   MyFile                     case_backup        old
1.jpg                 SOFTUPDATE                 case_history1009
ComenProcessorExport  SOFTUPDATE-2000light       case_history1012
Export                System Volume Information  gnasp_tool.tar.gz
root@imx6qsabresd:/var/volatile/tmp/udisk_sda1# sync
root@imx6qsabresd:/var/volatile/tmp/udisk_sda1# usb 2-1: USB disconnect, device number 2
FAT-fs (sda1): Directory bread(block 29632) failed
FAT-fs (sda1): Directory bread(block 29633) failed