C-equivalent of the 'setw' function

In c++, setw function is used to set the number of characters to be used as the field width for the next insertion operation.开发者_C百科 Is there any function in C, I mean, in standard c library, which does the same thing?

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printf ("%5d", 42);

Will print 42 using 5 spaces. Read the man pages of printf to understand how character padding, overflow and other nuances work.

EDIT: Some examples -

int x = 4000;
printf ("1234567890\n");
printf ("%05d\n", x);
printf ("%d\n", x);
printf ("%5d\n", x);
printf ("%2d\n", x);

Gives the output

1234567890
04000
4000
 4000
4000

Notice that the %2d was too small to handle the number passed to it, yet still printed the entire value.

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No, since the stream used in C doesn't maintain state the way the stream object does.

You need to specify with e.g. printf() using a suitable formatting code.

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Another option is to define the format string as a variable:

char print_format[] = "%5d"; printf(print_format, 42);

The above is similar to C++ setw, in that you can set the contents of the variable before printing. Many occasions require dynamic formatting of the output. This is one method to achieve it.

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setw Manipulator: This manipulator sets the minimum field width on output. The syntax is: setw(x) Here setw causes the number or string that follows it to be printed within a field of x characters wide and x is the argument set in setw manipulator. The header file that must be included while using setw manipulator is Sample Code

 #include <iostream>
 using namespace std;
 #include <iomanip> 
  
 void main( )
 {
 int x1=12345,x2= 23456, x3=7892;
 cout << setw(8) << "Exforsys" << setw(20) << "Values" << endl
         << setw(8) << "E1234567" << setw(20)<< x1 << endl
         << setw(8) << "S1234567" << setw(20)<< x2 << endl
         << setw(8) << "A1234567" << setw(20)<< x3 << endl;
 }