| NAME | SYNOPSIS | DESCRIPTION | CONFORMING TO | SEE ALSO | COLOPHON | The Linux Programming Interface |
ERROR(3) Linux Programmer's Manual ERROR(3)
error, error_at_line, error_message_count, error_on_per_line,
error_print_progname - glibc error reporting functions
#include <error.h>
void error(int status, int errnum, const char *format, ...);
void error_at_line(int status, int errnum, const char *filename,
unsigned int linenum, const char *format, ...);
extern unsigned int error_message_count;
extern int error_one_per_line;
extern void (* error_print_progname) (void);
error() is a general error-reporting function. It flushes stdout, and then
outputs to stderr the program name, a colon and a space, the message specified
by the printf(3)-style format string format, and, if errnum is nonzero, a
second colon and a space followed by the string given by strerror(errnum).
Any arguments required for format should follow format in the argument list.
The output is terminated by a newline character.
The program name printed by error() is the value of the global variable
program_invocation_name(3). program_invocation_name initially has the same
value as main()'s argv[0]. The value of this variable can be modified to
change the output of error().
If status has a nonzero value, then error() calls exit(3) to terminate the
program using the given value as the exit status.
The error_at_line() function is exactly the same as error(), except for the
addition of the arguments filename and linenum. The output produced is as for
error(), except that after the program name are written: a colon, the value of
filename, a colon, and the value of linenum. The preprocessor values __LINE__
and __FILE__ may be useful when calling error_at_line(), but other values can
also be used. For example, these arguments could refer to a location in an
input file.
If the global variable error_one_per_line is set nonzero, a sequence of
error_at_line() calls with the same value of filename and linenum will result
in only one message (the first) being output.
The global variable error_message_count counts the number of messages that
have been output by error() and error_at_line().
If the global variable error_print_progname is assigned the address of a
function (i.e., is not NULL), then that function is called instead of
prefixing the message with the program name and colon. The function should
print a suitable string to stderr.
These functions and variables are GNU extensions, and should not be used in
programs intended to be portable.
err(3), errno(3), exit(3), perror(3), program_invocation_name(3), strerror(3)
This page is part of release 3.32 of the Linux man-pages project. A
description of the project, and information about reporting bugs, can be found
at http://www.kernel.org/doc/man-pages/.
GNU 2010-08-29 ERROR(3)
HTML rendering created 2010-12-03 by Michael Kerrisk, author of The Linux Programming Interface