Block 132 I-node 26 Block 406 I-node 6 is /usr is for is /usr/ast Root directory is for /usr directory /usr/ast directory Open File Table 26 Mode Mode 1 6 i-node Curr. size size times times No. pos. 4 bin 19 dick 64 grants g年 7 dev 132 30 enk 406 92 books 7 free 14b 51 jim 60 mbox 9 etc 26 ast 81 minix 8 92 55 6 usr 45 bal 17 SrC 9 free 8 tmp Illustrate each of the following operations and show all changes to the data structure in the diagrams above. (a)open the file mbox:fd=open("/usr/ast/mbox") (b)seek to position 60 of the open mbox file:seek(fd,60) (c)close the file mbox:close(fd) 8.Following is a C program in Unix system. (a)Please give the notes for each system call. include <sys/types.h> include <signal.h> main ( A卷总8页第7页A 卷 总 8 页 第 7 页 free 9 8 7 92 55 free Open File Table Curr. pos. i-node No. ... ... ... ... Illustrate each of the following operations and show all changes to the data structure in the diagrams above. (a) open the file mbox: fd=open(“/usr/ast/mbox”) (b) seek to position 60 of the open mbox file: seek(fd,60) (c) close the file mbox: close(fd) 8. Following is a C program in Unix system. (a)Please give the notes for each system call. # include <sys/types.h> # include <signal.h> main ( ) {