LIBXO(3)               FreeBSD Library Functions Manual               LIBXO(3)

NAME
     xo_err, xo_errc, xo_errx xo_warn, xo_warnx, xo_warn_c, xo_warn_hc - emit
     errors and warnings in multiple output styles

LIBRARY
     Text, XML, JSON, and HTML Output Emission Library (libxo, -lxo)

SYNOPSIS
     #include <libxo/xo.h>

     void
     xo_warn(const char *fmt, ...);

     void
     xo_warnx(const char *fmt, ...);

     void
     xo_warn_c(int code, const char *fmt, ...);

     void
     xo_warn_hc(xo_handle_t *xop, int code, const char *fmt, ...);

     void
     xo_err(int eval, const char *fmt, ...);

     void
     xo_errc(int eval, int code, const char *fmt, ...);

     void
     xo_errx(int eval, const char *fmt, ...);

DESCRIPTION
     Many programs make use of the standard library functions err(3) and
     warn(3) to generate errors and warnings for the user.  libxo wants to
     pass that information via the current output style, and provides
     compatible functions to allow this.

     The fmt argument is one compatible with printf(3) rather than xo_emit(3)
     to aid in simple conversion.  This means these functions make
     unstructured data.  To generate structured data, use the xo_emit_err(3)
     functions.

     These functions display the program name, a colon, a formatted message
     based on the arguments, and then optionally a colon and an error message
     associated with either errno or the code parameter.

               EXAMPLE:
                   if (open(filename, O_RDONLY) < 0)
                       xo_err(1, "cannot open file '%s'", filename);

SEE ALSO
     xo_emit(3), xo_emit_err(3), libxo(3)

HISTORY
     The libxo library first appeared in FreeBSD 11.0.

AUTHORS
     libxo was written by Phil Shafer <phil@freebsd.org>.

FreeBSD 13.1-RELEASE-p6        December 4, 2014        FreeBSD 13.1-RELEASE-p6