Question

I have the following statement:

printf("name: %s	args: %s	value %d	arraysize %d
", sp->name, sp->args, sp->value, sp->arraysize);

I want to break it up. I tried the following but it doesn t work.

printf("name: %s	
args: %s	
value %d	
arraysize %d
", 
sp->name, 
sp->args, 
sp->value, 
sp->arraysize);

How can I break it up?

Answer 1

If you want to break a string literal onto multiple lines, you can concatenate multiple strings together, one on each line, like so:

printf("name: %s	"
"args: %s	"
"value %d	"
"arraysize %d
", 
sp->name, 
sp->args, 
sp->value, 
sp->arraysize);

Answer 2

The C compiler can glue adjacent string literals into one, like

printf("foo: %s "
       "bar: %d", foo, bar);

The preprocessor can use a backslash as a last character of the line, not counting CR (or CR/LF, if you are from Windowsland):

printf("foo %s 
bar: %d", foo, bar);

Answer 3

Just some other formatting options:

printf("name: %s	args: %s	value %d	arraysize %d
", 
        a,        b,        c,        d);

printf("name: %s	args: %s	value %d	arraysize %d
", 
              a,        b,        c,            d);

printf("name: %s	"      "args: %s	"      "value %d	"      "arraysize %d
", 
        very_long_name_a, very_long_name_b, very_long_name_c, very_long_name_d);

You can add variations on the theme. The idea is that the printf() conversion speficiers and the respective variables are all lined up "nicely" (for some values of "nicely").

Answer 4

The de-facto standard way to split up complex functions in C is per argument:

printf("name: %s	args: %s	value %d	arraysize %d
", 
       sp->name, 
       sp->args, 
       sp->value, 
       sp->arraysize);

Or if you will:

const char format_str[] = "name: %s	args: %s	value %d	arraysize %d
";
...
printf(format_str, 
       sp->name, 
       sp->args, 
       sp->value, 
       sp->arraysize);

You shouldn t split up the string, nor should you use to break a C line. Such code quickly turns completely unreadable/unmaintainable.

Answer 5

I don t think using one printf statement to print string literals as seen above is a good programming practice; rather, one can use the piece of code below:

printf("name: %s	",sp->name);
printf("args: %s	",sp->args);
printf("value: %s	",sp->value);
printf("arraysize: %s	",sp->name);

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