CPC_SETERRFN(3CPC)CPC_SETERRFN(3CPC)NAMEcpc_seterrfn - control libcpc error reporting
SYNOPSIS
cc [ flag... ] file... −lcpc [ library... ]
#include <libcpc.h>
typedef void (cpc_errfn_t)(const char *fn, const char *fmt, va_list ap);
void cpc_seterrfn(cpc_errfn_t *errfn);
DESCRIPTION
For the convenience of programmers instrumenting their code, several
libcpc(3LIB) functions automatically emit to stderr error messages that
attempt to provide a more detailed explanation of their error return
values. While this can be useful for simple programs, some applica‐
tions may wish to report their errors differently—for example, to a
window or to a log file.
The cpc_seterrfn() function allows the caller to provide an alternate
function for reporting errors; the type signature is shown above. The
fn argument is passed the library function name that detected the
error, the format string fmt and argument pointer ap can be passed
directly to vsnprintf(3C) or similar varargs-based routine for format‐
ting.
The default printing routine can be restored by calling the routine
with an errfn argument of NULL.
EXAMPLES
Example 1 Debugging example.
This example produces error messages only when debugging the program
containing it, or when the cpc_strtoevent() function is reporting an
error when parsing an event specification
int debugging;
void
myapp_errfn(const char *fn, const char *fmt, va_list ap)
{
if (strcmp(fn, "strtoevent") != 0 && !debugging)
return;
(void) fprintf(stderr, "myapp: cpc_%s(): ", fn);
(void) vfprintf(stderr, fmt, ap);
}
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌────────────────────┬─────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├────────────────────┼─────────────────┤
│MT-Level │ Unsafe │
├────────────────────┼─────────────────┤
│Interface Stability │ Obsolete │
└────────────────────┴─────────────────┘
SEE ALSOcpc(3CPC), cpc_seterrhndlr(3CPC), libcpc(3LIB), vsnprintf(3C),
attributes(5)NOTES
The cpc_seterrfn() function exists for binary compatibility only.
Source containing this function will not compile. This function is
obsolete and might be removed in a future release. Applications should
use cpc_seterrhndlr(3CPC) instead.
Mar 28, 2005 CPC_SETERRFN(3CPC)
