*** UNIX MANUAL PAGE BROWSER ***

A Nergahak database for man pages research.

Navigation

Directory Browser

1Browse 4.4BSD4.4BSD
1Browse Digital UNIXDigital UNIX 4.0e
1Browse FreeBSDFreeBSD 14.3
1Browse MINIXMINIX 3.4.0rc6-d5e4fc0
1Browse NetBSDNetBSD 10.1
1Browse OpenBSDOpenBSD 7.7
1Browse UNIX v7Version 7 UNIX
1Browse UNIX v10Version 10 UNIX

Manual Page Search

Manual Page Result

0 Command: fmtcheck | Section: 3 | Source: NetBSD | File: fmtcheck.3
FMTCHECK(3) FreeBSD Library Functions Manual FMTCHECK(3) NAME fmtcheck - sanitizes user-supplied printf(3)-style format string LIBRARY Standard C Library (libc, -lc) SYNOPSIS #include <stdio.h> const char * fmtcheck(const char *fmt_suspect, const char *fmt_default); DESCRIPTION The fmtcheck function scans fmt_suspect and fmt_default to determine if fmt_suspect will consume the same argument types as fmt_default and to ensure that fmt_suspect is a valid format string. The printf(3) family of functions can not verify the types of arguments that they are passed at run-time. In some cases, like catgets(3), it is useful or necessary to use a user-supplied format string with no guarantee that the format string matches the specified parameters. The fmtcheck function was designed to be used in these cases, as in: printf(fmtcheck(user_format, standard_format), arg1, arg2); In the check, field widths, fillers, precisions, etc. are ignored (unless the field width or precision is an asterisk `*' instead of a digit string). Also, any text other than the format specifiers is completely ignored. Note that the formats may be quite different as long as they accept the same parameters. For example, "%ld %o %30s %#llx %-10.*e %n" is compatible with "This number %lu %d%% and string %s has %qd numbers and %.*g floats (%n)." However, "%o" is not equivalent to "%lx" because the first requires an integer and the second requires a long, and "%p" is not equivalent to "%lu" because the first requires a pointer and the second requires a long. RETURN VALUES If fmt_suspect is a valid format and consumes the same argument types as fmt_default, then the fmtcheck function will return fmt_suspect. Otherwise, it will return fmt_default. SEE ALSO printf(3) FreeBSD 14.1-RELEASE-p8 June 14, 2014 FreeBSD 14.1-RELEASE-p8

Navigation Options