diff options
Diffstat (limited to 'man3/printf.3')
| -rw-r--r-- | man3/printf.3 | 102 |
1 files changed, 65 insertions, 37 deletions
diff --git a/man3/printf.3 b/man3/printf.3 index 763b5e2a27..790ebf4d8f 100644 --- a/man3/printf.3 +++ b/man3/printf.3 @@ -919,7 +919,70 @@ T} Thread safety MT-Safe locale .hy .ad .sp 1 -.SH VERSIONS +.SH STANDARDS +.TP +.BR fprintf () +.TQ +.BR printf () +.TQ +.BR sprintf () +.TQ +.BR vprintf () +.TQ +.BR vfprintf () +.TQ +.BR vsprintf () +.TQ +.BR snprintf () +.TQ +.BR vsnprintf () +C11, POSIX.1-2008. +.TP +.BR dprintf () +.TQ +.BR vdprintf () +GNU, POSIX.1-2008. +.SH HISTORY +.TP +.BR fprintf () +.TQ +.BR printf () +.TQ +.BR sprintf () +.TQ +.BR vprintf () +.TQ +.BR vfprintf () +.TQ +.BR vsprintf () +C89, POSIX.1-2001. +.TP +.BR snprintf () +.TQ +.BR vsnprintf () +SUSv2, C99, POSIX.1-2001. +.IP +Concerning the return value of +.BR snprintf (), +SUSv2 and C99 contradict each other: when +.BR snprintf () +is called with +.IR size =0 +then SUSv2 stipulates an unspecified return value less than 1, +while C99 allows +.I str +to be NULL in this case, and gives the return value (as always) +as the number of characters that would have been written in case +the output string has been large enough. +POSIX.1-2001 and later align their specification of +.BR snprintf () +with C99. +.TP +.BR dprintf () +.TQ +.BR vdprintf () +GNU, POSIX.1-2008. +.PP .\" Linux libc4 knows about the five C standard flags. .\" It knows about the length modifiers \fBh\fP, \fBl\fP, \fBL\fP, .\" and the conversions @@ -959,42 +1022,7 @@ of the .B m conversion specifier, that is .IR %#m . -.SH STANDARDS -.BR fprintf (), -.BR printf (), -.BR sprintf (), -.BR vprintf (), -.BR vfprintf (), -.BR vsprintf (): -POSIX.1-2001, POSIX.1-2008, C89, C99. -.PP -.BR snprintf (), -.BR vsnprintf (): -POSIX.1-2001, POSIX.1-2008, C99. -.PP -The -.BR dprintf () -and -.BR vdprintf () -functions were originally GNU extensions that were later standardized -in POSIX.1-2008. -.PP -Concerning the return value of -.BR snprintf (), -SUSv2 and C99 contradict each other: when -.BR snprintf () -is called with -.IR size =0 -then SUSv2 stipulates an unspecified return value less than 1, -while C99 allows -.I str -to be NULL in this case, and gives the return value (as always) -as the number of characters that would have been written in case -the output string has been large enough. -POSIX.1-2001 and later align their specification of -.BR snprintf () -with C99. -.SH NOTES +.SH CAVEATS Some programs imprudently rely on code such as the following .PP .in +4n |