verr(), verrx()

Updated: April 19, 2023

Display a formatted error message, and then exit (varargs)

Synopsis:

#include <err.h>

void verr( int eval, 
           const char *fmt,
           va_list args );

void verrx( int eval, 
            const char *fmt,
            va_list args );

Arguments:

eval
The value to use as the exit code of the process.
fmt
NULL, or a printf()-style string used to format the message.
args
A variable-argument list of the additional arguments, which you must have initialized with the va_start() macro.

Library:

libc

Use the -l c option to qcc to link against this library. This library is usually included automatically.

Description:

The err() and warn() family of functions display a formatted error message on stderr. For a comparison of the members of this family, see err().

The verr() function produces a message that consists of:

The verrx() function produces a similar message, except that it doesn't include the string associated with errno. The message consists of:

The verr() and verrx() functions don't return, but exit with the value of the argument eval.

Classification:

Unix

Safety:  
Cancellation point Yes
Interrupt handler No
Signal handler Yes
Thread Yes