diff options
Diffstat (limited to '1088/CH23/EX23.3')
| -rwxr-xr-x | 1088/CH23/EX23.3/Example3.sce | 72 | ||||
| -rwxr-xr-x | 1088/CH23/EX23.3/Result3.txt | 87 |
2 files changed, 159 insertions, 0 deletions
diff --git a/1088/CH23/EX23.3/Example3.sce b/1088/CH23/EX23.3/Example3.sce new file mode 100755 index 000000000..95443c251 --- /dev/null +++ b/1088/CH23/EX23.3/Example3.sce @@ -0,0 +1,72 @@ +clear +flag=1 +mode(-1) +clc + +printf("Example 3 : Show the effect of umask on permissions of a file \n") +disp("****************************************************************") +disp("Answer : ") +disp("INSTRUCTIONS : ") +halt(' ') +disp("1.These programs are part of systems programming in Unix and the commands have NO EQUIVALENT IN SCILAB") +halt(' ') +disp('2.However if possible some selected programmes have been TRIED TO BE IMPLEMENTED') +halt("") +disp('3.For most of the programmes whose equivalent is NOT THERE IN SCILAB,only the output has been printed as given in the textbook with no interactive input as in the programme below') +halt("") +disp("4.However the .c files which are displayed here are also made into a seperate file.If you are a unix user then try compiling and running the programme with gcc or cc compiler") +disp("5.The inconvenience is regretted.") +halt('.............Press [ENTER] to continue.....') +halt("") +clc +printf("\tUNIX SHELL SIMULATOR(DEMO VERSION WITH PRELOADED COMMANDS)\n\n\n") +i=0 +i=i+1;f(i)='/* Program: umask.c -- Changes umask twice and checks effect on permissions */' +i=i+1;f(i)='' +i=i+1;f(i)='#include <stdio.h>' +i=i+1;f(i)='#include <fcntl.h>' +i=i+1;f(i)='' +i=i+1;f(i)='int main(void) {' +i=i+1;f(i)=' mode_t old_mode,new_mode;' +i=i+1;f(i)=' ' +i=i+1;f(i)=' old_mode = umask(0); /* No mask */' +i=i+1;f(i)=' printf('+ascii(34)+'Previous umask value: %o\n'+ascii(34)+', old_mode);' +i=i+1;f(i)=' ' +i=i+1;f(i)=' open('+ascii(34)+'foo1'+ascii(34)+',O_RDONLY | O_CREAT, 0777); /* Create file using new mask */' +i=i+1;f(i)=' umask(old_mode); /* Revert to previous mask */' +i=i+1;f(i)=' open('+ascii(34)+'foo2'+ascii(34)+',O_RDWR | O_CREAT, 0764); /* Create file using old mask */' +i=i+1;f(i)=' exit(0);' +i=i+1;f(i)='} ' +n=i + +printf("\n\n$ cat umask.c # to open the file emp.lst") +halt(' ') +u=mopen('umask.c','wt') +for i=1:n + mfprintf(u,"%s\n",f(i)) + printf("%s\n",f(i)) +end +mclose(u) +halt('') +clc + +halt(' ') + printf("$ cc umask.c") + halt(' ') + printf("$ a.out") + halt(' ') + printf("Previous umask value: 22") + halt(' ') + printf("$ ls -l foo?") + halt(' ') +disp("-rwxrwxrwx 1 sumit sumit 0 Dec 1 12:01 foo1") +disp("-rwxr--r-- 1 sumit sumit 0 Dec 1 12:01 foo2") +halt(' ') +printf("\n\n\n$ exit #To exit the current simulation terminal and return to Scilab console\n\n") +halt("........# (hit [ENTER] for result)") +//clc() + +printf("\n\n\t\t\tBACK TO SCILAB CONSOLE...\nLoading initial environment') +sleep(1000) + + diff --git a/1088/CH23/EX23.3/Result3.txt b/1088/CH23/EX23.3/Result3.txt new file mode 100755 index 000000000..39a1c4e08 --- /dev/null +++ b/1088/CH23/EX23.3/Result3.txt @@ -0,0 +1,87 @@ + ans =
+
+ 1.
+
+-->exec('Example3.sci')
+
+-->clear
+
+-->flag=1
+ flag =
+
+ 1.
+
+-->mode(-1)
+Current date is 23-Jun-2013
+
+Welcome to the Textbook Companionship Project 2013
++-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+
+ Book Title : UNIX CONCEPTS AND APPLICATIONS
+
+ Book Edition : 4
+
+ Book Author : Sumitabha Das
++-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+
+ Code Author : Pranav Bhat T
++-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+
+ Chapter Number : 23
+
+ Chapter Title : Systems programming I- Files
++-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+Example 3 : Show the effect of umask on permissions of a file
+
+ ****************************************************************
+
+ Answer :
+
+ INSTRUCTIONS :
+
+ 1.These programs are part of systems programming in Unix and the commands have NO EQUIVALENT IN SCILAB
+
+ 2.However if possible some selected programmes have been TRIED TO BE IMPLEMENTED
+
+ 3.For most of the programmes whose equivalent is NOT THERE IN SCILAB,only the output has been printed as given in the textbook w
+ ith no interactive input as in the programme below
+
+ 4.However the .c files which are displayed here are also made into a seperate file.If you are a unix user then try compiling and
+ running the programme with gcc or cc compiler
+
+ 5.The inconvenience is regretted.
+.............Press [ENTER] to continue..... UNIX SHELL SIMULATOR(DEMO VERSION WITH PRELOADED COMMANDS)
+
+
+
+
+$ cat umask.c # to open the file emp.lst /* Program: umask.c -- Changes umask twice and checks effect on permissions */
+
+#include <stdio.h>
+#include <fcntl.h>
+
+int main(void) {
+ mode_t old_mode,new_mode;
+
+ old_mode = umask(0); /* No mask */
+ printf("Previous umask value: %o\n", old_mode);
+
+ open("foo1",O_RDONLY | O_CREAT, 0777); /* Create file using new mask */
+ umask(old_mode); /* Revert to previous mask */
+ open("foo2",O_RDWR | O_CREAT, 0764); /* Create file using old mask */
+ exit(0);
+}
+ $ cc umask.c $ a.out Previous umask value: 22 $ ls -l foo?
+ -rwxrwxrwx 1 sumit sumit 0 Dec 1 12:01 foo1
+
+ -rwxr--r-- 1 sumit sumit 0 Dec 1 12:01 foo2
+
+
+
+$ exit #To exit the current simulation terminal and return to Scilab console
+
+........# (hit [ENTER] for result)
+
+ BACK TO SCILAB CONSOLE...
+Loading initial environment
+-->diary(0)
|