Looking for a Tutor Near You?

Post Learning Requirement »
x

Choose Country Code

x

Direction

x

Ask a Question

x

x
x
For better view click here
x
Hire a Tutor
DISCOVER

C Language

Loading...

Published in: C / C++
1,140 Views

Simplified Concepts And Implementation of C.

Suman / Gurgaon

6 years of teaching experience

Qualification: B.Tech

Teaches: Computer, IT, C / C++, Java And J2EE, Python Programming, MCA Subjects, Networking, Software Testing, Unix/Linux

Contact this Tutor
  1. Structures & Unions Heterogenous collection of items. Structures are derived types as per C language. struct struct tag { int a; char b; Struct _ tag is a new type using which can be declrared further. variables (objects) struct struct _ tag objectl, object 2, struct struct tag { int char b; No memory allocated so compilation error int i struct struct tag { int a; char b; object3; 'p'}; struct struct struct struct struct struct output: printf( printf( Input: scanf ( " scanf ( " &sl.b = operator: sl.a sl.b tag tag tag sl.a); sl.b); &sl.a); &sl.b); &(sl.b) Binary operator. Requires a Structure OR union object on the left side and a filed name from the structure or union on the right side. struct struct tag *sp=&sl; struct struct _ tag sp is a pointer to struct struct _ tag. - > operator
  2. sp b sp sp->a) sp->b) &sp->a) &sp->b); sl s2 10 x' printf( printf( Input : scanf ( " scanf ( "%c\n" , &sp->b printf( printf( &(sp->b) sl.a); sl.b); struct struct tag { int a ; char b ; print the fields of SI, s2 and s3. a'}, x'}, s3; sl sl - //Error //Error //Error VALID sizeof of structure: struct X { int a ; char b; struct X { int a ; char b ; int c ; struct X { int a; char b ; char bl; int c ; struct X { int a ; char b ; short bl; int c ; struct X { int a ;
  3. char b; char bl; short b2; int c; struct X { int a; char b; short b2; int c; char bl; struct X { int a; char b; struct X { short a; char b; struct X { short a; char b; char bl; struct X { char bl; short a; char b; bl--l padding 5 b bl b 2 1 --1 2 1 4 so uniformly size is set at 6 Array of structures: struct X x [4] • b field of the 4 th object in the array: Read the values for all the fields of x and display back to the screen
  4. Arrays in structures: struct student { int id; char name [20] • int marks[3] • struct student sl,s2; second subject marks of student one sl.marks[l] scanf &sl.marks[i] scanf ( "%19s " , sl . name) ; f gets(sl. name, sizeof(sl. name), Structures within structures: X { int a; char b;} stdin); struct Y { int a; struct struct X x; char b; ---- int struct X int char char Y { int a; struct struct X x; char b; { 10, {20, 20 'P' 'q' struct y.x.a---2@ struct y.x.a---2@ struct 'p'}/ 'q'} Y { int a; struct X x; char b; { 10, {20}, 'q' Y { int a; struct X x; char b; { 10, 20, 'q' Y { int a;
  5. struct X x; char b; { 10, {20, y.x.a---2@ 'q' Incomplete structures: x' 'Y'} struct X struct X x; // Incomplete struct. // ERROR struct X * xp=NULL; // VALID Size of Pointer XP is not dependent on sizeof(struct X) sizeof( XP) will sizeof( struct X struct X { int a; struct X x; sizeof( struct X struct X { int a; struct Y { int a; be pointer size. . ) and sizeof( *XP) are unknown... char b; } ; // struct X COMPLETED NOT AN ERROR ) and sizeof( *XP) ARE KNOWN. . char b;} struct Y x; char b; compilation error Self containing structures-- struct Y { int a; struct Y *sp; char b; pointer Y. sp self referential structures struct X struct X struct { int a; { int a; { int a; No further objects struct { int a; char b;} x; char b;} ; char b;} xl; of type xl can char b;} xl,x2,x3, not permitted in C allowed in C // tag & object // tag // object be created. // valid objects single- ton obj ects struct X { int a; char b;} struct X *xp; Pointer to a single ton object;
  6. struct &xl &xl->a &(xl->a) ERROR xl.b { int a; char b;} Ptr to object xl xl x'}, *xp; // object (&xl) ->a (&xl) ->b XP = &xl; xp->a xp->b -30 x' 30 x' differing types: struct X { int a}x; struct Y { int a}y; int i; x and i are of differing types. struct X is a different type from struct Y x and i; x i=x.a; y are of differing types. // ERROR // ERROR VALID. Optimizing on Structure size: struct X { char a; int b; char c; Bit fields: struct X { int int b: 20; struct X { int a: 1; int b: 2;
  7. 1 1 sign 1 sign Use unsigned bit bit bit fields 1 1 data sizeof(x) sizeof(y) 1 -2 -1 -1 struct X { int a: 20; int b: 15; union X { int a char b: struct Y { int a char b: print &x, &x.a, &x b print &y, &y.a, print x. a with %x print x. b with %hhx Space for the largest field is allocated. Alignment : With respect to all the fields union Query { int id; char name [20] q. id bytes q . name // No point using name when id is filled
  8. q. name:" hello" strcpy(q. name, ' q. id No Linkage for 1) filel.c struct X{ //ERROR 'hello"); No point using id when name is filled Tags... OR typedef. . file2 . c int a; char b; filel.c struct X{ int a; char b; filel.c struct X{ int a; char b; void f (void) printf("%p\n" //ERROR struct X x; main() { } file2 . c extern struct X; // Incomplete struct, // No linkage //ERROR struct X x; main() { } file2 . c struct X { int a; char b;} ; exten struct X x; int main(void) print f ("main: %p\n" VLAs in structures? int a=3; struct X { int p[a]; char b} x; gcc does support VLAs in structures..
  9. int int i -i, struct X xp->a-- xp->b-- j=i; { int a; char b} equal 10 equal 'a' x2, *xp=&xl;

Need a Tutor or Coaching Class?

Post an enquiry and get instant responses from qualified and experienced tutors.

Post Requirement

Related Study Notes

Upload Study Notes

If you have your own Study Notes which you think can benefit others, please upload on LearnPick. For each approved Study Note you will get 100 Credit Points and 100 Activity Score which will increase your profile visibility.

Upload Now
Home > Study Notes > C Language