Updated: April 19, 2023 |
Formatted error message
#include <err.h> void warn( const char* fmt, ...); void warnx( const char* fmt, ...);
libc
Use the -l c option to qcc to link against this library. This library is usually included automatically.
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 warn() function produces a message that consists of:
The warnx() function produces a similar message, except that it doesn't include the string associated with errno. The message consists of:
Warn of an error:
if ((fd = open(raw_device, O_RDONLY, 0)) == -1) warnx("%s: %s: trying the block device", raw_device, strerror(errno)); if ((fd = open(block_device, O_RDONLY, 0)) == -1) warn("%s", block_device);
Safety: | |
---|---|
Cancellation point | Yes |
Interrupt handler | No |
Signal handler | Yes |
Thread | Yes |