BEAUTY AND PLAY
GNU command $ls -l -Gg total 124 -rwxr-xr-x 1 54161 Dec 12 18:32 bp -rw-r–r– 1 8917 Sep 22 2006 cfg.c -rw-r–r– 1 1638 Sep 22 2006 cfg.h drwxr-xr-x 2 4096 Oct 26 17:43 CVS drwxr-xr-x 3 4096 Oct 26 00:48 gtk -rw-r–r– 1 104 Oct 26 00:49 Makefile -rw-r–r– 1 718 Dec 12 18:33 …
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GNU command $ls -l total 40 drwxr-xr-x 3 jeffrin jeffrin 4096 Aug 18 20:16 beautifulwork drwxr-xr-x 5 jeffrin jeffrin 4096 Aug 18 20:16 books drwxr-xr-x 2 jeffrin jeffrin 4096 Aug 18 20:16 bugs-general drwxr-xr-x 2 jeffrin jeffrin 4096 Oct 13 20:27 config-files drwxr-xr-x 3 jeffrin jeffrin 4096 Aug 24 22:03 debian-howtos drwxr-xr-x 2 jeffrin jeffrin …
UNIX Command $ls -l –author Cairo-0.2.0.tgz -rw-r–r– 1 jeffrin jeffrin jeffrin 164022 Oct 20 21:05 Cairo-0.2.0.tgz $ls -l Cairo-0.2.0.tgz -rw-r–r– 1 jeffrin jeffrin 164022 Oct 20 21:05 Cairo-0.2.0.tgz $ UNIX Explanation –author with -l, print the author of each file
1. __generic_file_aio_write – write data to a file ssize_t __generic_file_aio_write(struct kiocb * iocb, const struct iovec * iov, unsigned long nr_segs, loff_t * ppos); iocb IO state structure (file, offset, etc.) iov vector with data to write nr_segs number of segments in the vector ppos position where to write 2. Classroom Asynchronous I/O, or non-blocking …
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UNIX Command $cat hello.c #include main() { int d; scanf(“%d”,d); printf(“%d”,d); } $gcc hello.c $ulimit -c unlimited $./a.out 3 Segmentation fault (core dumped) $readelf -s core $readelf -a core ELF Header: Magic: 7f 45 4c 46 02 01 01 00 00 00 00 00 00 00 00 00 Class: ELF64 Data: 2’s complement, little endian …
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1. vm_insert_page – insert single page into user vma int vm_insert_page(struct vm_area_struct * vma, unsigned long addr, struct page * page); vma user vma to map to addr target user address of this page page source kernel page 2. Classroom The virtual memory area (VMA) is the kernel data structure used to manage distinct regions …
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UNIX Command $grep -c pack resume.txt 0 $grep -c Linux resume.txt 9 $grep -c Lin resume.txt 9 $grep -c Li resume.txt 9 $grep -c L resume.txt 15 $grep -c engineer resume.txt 2 $grep -c 1976 resume.txt 1 $grep -c GNU resume.txt 5 $ UNIX Explanation For (grep -c) Suppress normal output; instead print a count …
1.Classroom maps Memory maps to executables and library files Get The Hang $sudo cat /proc/971/maps 00400000-00408000 r-xp 00000000 08:01 7422174 /sbin/syslogd 00607000-00608000 rw-p 00007000 08:01 7422174 /sbin/syslogd 00608000-00609000 rw-p 00000000 00:00 0 01429000-0144a000 rw-p 00000000 00:00 0 [heap] 7fd360fa5000-7fd360fb0000 r-xp 00000000 08:01 1466895 /lib/x86_64-linux-gnu/libnss_files-2.13.so 7fd360fb0000-7fd3611af000 —p 0000b000 08:01 1466895 /lib/x86_64-linux-gnu/libnss_files-2.13.so 7fd3611af000-7fd3611b0000 r–p 0000a000 08:01 1466895 …
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1. mca_disable_dma – channel to disable DMA on void mca_disable_dma(unsigned int dmanr); dmanr DMA channel 2. Classroom First of all, DMA (per se) is almost entirely obsolete. As originally defined, DMA controllers depended on thefact that the bus had separate lines to assert for memory read/write, and I/O read/write. The DMA controller took advantage of …
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1. write_inode_now – write an inode to disk This function commits an inode to disk immediately if it is dirty. This is primarily needed by knfsd.