printf.3s (2010 09)

printf(3S) printf(3S)

[EFBIG] An attempt was made to write to a ﬁle that exceeds the process’s ﬁle size limit or the

maximum ﬁle size (see ulimit (2)).

[EINTR] A signal was caught during the

write() system call.

[EIO] The process is in a background process group and is attempting to write to its controlling

terminal,

TOSTOP is set, the process is neither ignoring nor blocking the

SIGTTOU sig-

nal, and the process group of the process is orphaned.

[ENOSPC] There was no free space remaining on the device containing the ﬁle.

[EPIPE] An attempt is made to write to a pipe or FIFO that is not open for reading by any process.

SIGPIPE signal is also sent to the process.

[EILSEQ] The data obtained from the input stream does not form a valid wide character.

[ENOMEM] Insufﬁcient storage space is available.

Additional

errno values can be set by the underlying

write() function (see write (2)).

EXAMPLES

To print a date and time in the form "Sunday, July 3, 10:02", where weekday and month are pointers to

null-terminated strings:

printf("%s, %s %d, %d:%.2d", weekday, month, day, hour, min);

To print Pi to 5 decimal places:

printf("Pi = %.5f", 4 * atan(1.0));

To create a language independent date-and-time printing routine write:

printf(format,weekday,month,day,hour,min,2,2);

For American usage, format would point to the string:

"%1$s, %2$s %3$d, %4$*6$.*7$d:%5$*6$.*7$d"

and result in the output:

"Sunday, July 3, 10:02"

For German usage, the string:

"%1$s, %3$s %2$d, %4$*6$.*7$d:%5$*6$.*7$d"

results in the output:

Sonntag, 3 Juli 10:02

WARNINGS

Notice that with the c conversion character, an int arg is converted to an unsigned char. Hence, whole

multibyte characters cannot be printed using a single c conversion character.

A precision with the

s conversion character might result in the truncation of a multibyte character.

Use of a conversion character which doesn’t match the type of the corresponding argument passed in will

result in invalid data being returned. For example, the modifying

ll, specifying that the following d, i,

o, u, x,orX conversion character applies to a long long integer arg, is necessary for proper results when

the argument is a long long integer.

AUTHOR

printf(), fprintf(), and sprintf() were developed by AT&T and HP.