diff options
| author | Ingo Schwarze <schwarze@cvs.openbsd.org> | 2019-06-27 11:53:00 +0000 |
|---|---|---|
| committer | Ingo Schwarze <schwarze@cvs.openbsd.org> | 2019-06-27 11:53:00 +0000 |
| commit | 41d89c1d2c7403fe1291a13d6cf38dfc23f1f6b1 (patch) | |
| tree | 95a6c02f0299d88483c810e96ea6dd1eecc0e066 /lib/libc/stdio/printf.3 | |
| parent | 7beb23dc86ff25032ccd398a4352fd52136db354 (diff) | |
Simplify the description of [v]snprintf(3), move the description
of the return values to RETURN VALUES, deprecate [v]sprintf(3)
and fix a punctuation typo.
Joint work with and OK millert@.
Diffstat (limited to 'lib/libc/stdio/printf.3')
| -rw-r--r-- | lib/libc/stdio/printf.3 | 37 |
1 files changed, 18 insertions, 19 deletions
diff --git a/lib/libc/stdio/printf.3 b/lib/libc/stdio/printf.3 index ac2e35e8650..88dddcba4d3 100644 --- a/lib/libc/stdio/printf.3 +++ b/lib/libc/stdio/printf.3 @@ -1,4 +1,4 @@ -.\" $OpenBSD: printf.3,v 1.81 2019/06/26 22:40:05 jmc Exp $ +.\" $OpenBSD: printf.3,v 1.82 2019/06/27 11:52:59 schwarze Exp $ .\" .\" Copyright (c) 1990, 1991, 1993 .\" The Regents of the University of California. All rights reserved. @@ -33,7 +33,7 @@ .\" .\" @(#)printf.3 8.1 (Berkeley) 6/4/93 .\" -.Dd $Mdocdate: June 26 2019 $ +.Dd $Mdocdate: June 27 2019 $ .Dt PRINTF 3 .Os .Sh NAME @@ -129,32 +129,27 @@ are converted for output. .Fn snprintf and .Fn vsnprintf -will write at most +write at most .Fa size Ns \-1 -of the characters printed into the output string -(the -.Fa size Ns 'th -character then gets the terminating -.Ql \e0 ) ; -if the return value is greater than or equal to the -.Fa size -argument, the string was too short -and some of the printed characters were discarded. +characters to +.Fa str , +followed by a terminating +.Ql \e0 . If .Fa size is zero, +no characters are written and .Fa str -may be a null pointer and no characters will be written; -the number of bytes that would have been written excluding the terminating -.Ql \e0 -byte, or \-1 on error, will be returned (but due to a weakness in POSIX -should be checked with < 0). +may be a +.Dv NULL +pointer. .Pp .Fn sprintf and .Fn vsprintf effectively assume an infinite -.Fa size . +.Fa size ; +their use is not recommended. .Pp The format string is composed of zero or more directives: ordinary @@ -673,8 +668,12 @@ been output if the were unlimited .Po again, not including the final -.Ql \e0 . +.Ql \e0 .Pc . +A return value greater than or equal to the +.Fa size +argument indicates that the string was too small and some characters +were discarded. .Pp The .Fn asprintf |