In C can a long printf statement be broken up into multiple lines?

CPrintf

C Problem Overview


I have the following statement:

printf("name: %s\targs: %s\tvalue %d\tarraysize %d\n", 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\t
args: %s\t
value %d\t
arraysize %d\n", 
sp->name, 
sp->args, 
sp->value, 
sp->arraysize);

How can I break it up?

C Solutions


Solution 1 - C

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\t"
"args: %s\t"
"value %d\t"
"arraysize %d\n", 
sp->name, 
sp->args, 
sp->value, 
sp->arraysize);

Solution 2 - C

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);

Solution 3 - C

Just some other formatting options:

printf("name: %s\targs: %s\tvalue %d\tarraysize %d\n", 
        a,        b,        c,        d);

printf("name: %s\targs: %s\tvalue %d\tarraysize %d\n", 
              a,        b,        c,            d);

printf("name: %s\t"      "args: %s\t"      "value %d\t"      "arraysize %d\n", 
        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").

Solution 4 - C

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

printf("name: %s\targs: %s\tvalue %d\tarraysize %d\n", 
       sp->name, 
       sp->args, 
       sp->value, 
       sp->arraysize);

Or if you will:

const char format_str[] = "name: %s\targs: %s\tvalue %d\tarraysize %d\n";
...
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.

Solution 5 - C

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

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Content TypeOriginal AuthorOriginal Content on Stackoverflow
QuestionneuromancerView Question on Stackoverflow
Solution 1 - CJames McNellisView Answer on Stackoverflow
Solution 2 - CqrdlView Answer on Stackoverflow
Solution 3 - CpmgView Answer on Stackoverflow
Solution 4 - CLundinView Answer on Stackoverflow
Solution 5 - Cantoine maboulaView Answer on Stackoverflow