SYNOPSIS<\/a>
DESCRIPTION<\/a>
ATTRIBUTES<\/a>
CONFORMING TO<\/a>
SEE ALSO<\/a>
COLOPHON<\/a> <\/p>\n
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NAME <\/a> <\/h2>\nerror, error_at_line, error_message_count, error_one_per_line, error_print_progname \u2212 glibc error reporting functions<\/p>\n
SYNOPSIS <\/a> <\/h2>\n#include <\/b><\/p>\nvoid error(int<\/b> status<\/i>, int<\/b> errnum<\/i>, const char *<\/b>format<\/i>, …);<\/b><\/p>\n
void error_at_line(int<\/b> status<\/i>, int<\/b> errnum<\/i>, const char *<\/b>filename<\/i>,
unsigned int<\/b> linenum<\/i>, const char *<\/b>format<\/i>, …);<\/b><\/p>\n
extern unsigned int<\/b> error_message_count<\/i>;<\/b><\/p>\n
extern int<\/b> error_one_per_line<\/i>;<\/b><\/p>\n
extern void (*<\/b>error_print_progname<\/i>) (void);<\/b><\/p>\nDESCRIPTION <\/a> <\/h2>\nerror<\/b>() is a general error-reporting function. It flushes stdout<\/i>, and then outputs to stderr<\/i> the program name, a colon and a space, the message specified by the printf<\/b>(3)-style format string format<\/i>, and, if errnum<\/i> is nonzero, a second colon and a space followed by the string given by strerror(errnum)<\/i>. Any arguments required for format<\/i> should follow format<\/i> in the argument list. The output is terminated by a newline character.<\/p>\n
The program name printed by error<\/b>() is the value of the global variable program_invocation_name<\/b>(3). program_invocation_name<\/i> initially has the same value as main<\/i>()\u2019s argv[0]<\/i>. The value of this variable can be modified to change the output of error<\/b>().<\/p>\n
If status<\/i> has a nonzero value, then error<\/b>() calls exit<\/b>(3) to terminate the program using the given value as the exit status.<\/p>\n
The error_at_line<\/b>() function is exactly the same as error<\/b>(), except for the addition of the arguments filename<\/i> and linenum<\/i>. The output produced is as for error<\/b>(), except that after the program name are written: a colon, the value of filename<\/i>, a colon, and the value of linenum<\/i>. The preprocessor values __LINE__<\/b> and __FILE__<\/b> may be useful when calling error_at_line<\/b>(), but other values can also be used. For example, these arguments could refer to a location in an input file.<\/p>\n
If the global variable error_one_per_line<\/i> is set nonzero, a sequence of error_at_line<\/b>() calls with the same value of filename<\/i> and linenum<\/i> will result in only one message (the first) being output.<\/p>\n
The global variable error_message_count<\/i> counts the number of messages that have been output by error<\/b>() and error_at_line<\/b>().<\/p>\n
If the global variable error_print_progname<\/i> 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<\/i>.<\/p>\nATTRIBUTES <\/a> <\/h2>\nFor an explanation of the terms used in this section, see attributes<\/b>(7).<\/p>\n\n\n<\/td>\n <\/td>\n <\/td>\n <\/td>\n <\/td>\n <\/td>\n<\/tr>\n \n<\/td>\n <\/td>\n <\/td>\n <\/td>\n <\/td>\n <\/td>\n<\/tr>\n \n<\/td>\n <\/td>\n <\/td>\n <\/td>\n <\/td>\n \n\u00a0<\/p>\n<\/td>\n<\/tr>\n<\/table>\n
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The internal error_one_per_line<\/i> variable is accessed (without any form of synchronization, but since it\u2019s an int<\/i> used once, it should be safe enough) and, if error_one_per_line<\/i> is set nonzero, the internal static variables (not exposed to users) used to hold the last printed filename and line number are accessed and modified without synchronization; the update is not atomic and it occurs before disabling cancellation, so it can be interrupted only after one of the two variables is modified. After that, error_at_line<\/b>() is very much like error<\/b>().<\/p>\nCONFORMING TO <\/a> <\/h2>\nThese functions and variables are GNU extensions, and should not be used in programs intended to be portable.<\/p>\n
SEE ALSO <\/a> <\/h2>\n
#include void error(int<\/b> status<\/i>, int<\/b> errnum<\/i>, const char *<\/b>format<\/i>, …);<\/b><\/p>\n void error_at_line(int<\/b> status<\/i>, int<\/b> errnum<\/i>, const char *<\/b>filename<\/i>, extern unsigned int<\/b> error_message_count<\/i>;<\/b><\/p>\n extern int<\/b> error_one_per_line<\/i>;<\/b><\/p>\n extern void (*<\/b>error_print_progname<\/i>) (void);<\/b><\/p>\n error<\/b>() is a general error-reporting function. It flushes stdout<\/i>, and then outputs to stderr<\/i> the program name, a colon and a space, the message specified by the printf<\/b>(3)-style format string format<\/i>, and, if errnum<\/i> is nonzero, a second colon and a space followed by the string given by strerror(errnum)<\/i>. Any arguments required for format<\/i> should follow format<\/i> in the argument list. The output is terminated by a newline character.<\/p>\n The program name printed by error<\/b>() is the value of the global variable program_invocation_name<\/b>(3). program_invocation_name<\/i> initially has the same value as main<\/i>()\u2019s argv[0]<\/i>. The value of this variable can be modified to change the output of error<\/b>().<\/p>\n If status<\/i> has a nonzero value, then error<\/b>() calls exit<\/b>(3) to terminate the program using the given value as the exit status.<\/p>\n The error_at_line<\/b>() function is exactly the same as error<\/b>(), except for the addition of the arguments filename<\/i> and linenum<\/i>. The output produced is as for error<\/b>(), except that after the program name are written: a colon, the value of filename<\/i>, a colon, and the value of linenum<\/i>. The preprocessor values __LINE__<\/b> and __FILE__<\/b> may be useful when calling error_at_line<\/b>(), but other values can also be used. For example, these arguments could refer to a location in an input file.<\/p>\n If the global variable error_one_per_line<\/i> is set nonzero, a sequence of error_at_line<\/b>() calls with the same value of filename<\/i> and linenum<\/i> will result in only one message (the first) being output.<\/p>\n The global variable error_message_count<\/i> counts the number of messages that have been output by error<\/b>() and error_at_line<\/b>().<\/p>\n If the global variable error_print_progname<\/i> 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<\/i>.<\/p>\n For an explanation of the terms used in this section, see attributes<\/b>(7).<\/p>\n \u00a0<\/p>\n<\/td>\n<\/tr>\n<\/table>\n The internal error_one_per_line<\/i> variable is accessed (without any form of synchronization, but since it\u2019s an int<\/i> used once, it should be safe enough) and, if error_one_per_line<\/i> is set nonzero, the internal static variables (not exposed to users) used to hold the last printed filename and line number are accessed and modified without synchronization; the update is not atomic and it occurs before disabling cancellation, so it can be interrupted only after one of the two variables is modified. After that, error_at_line<\/b>() is very much like error<\/b>().<\/p>\n These functions and variables are GNU extensions, and should not be used in programs intended to be portable.<\/p>\n
unsigned int<\/b> linenum<\/i>, const char *<\/b>format<\/i>, …);<\/b><\/p>\nDESCRIPTION <\/a> <\/h2>\n
ATTRIBUTES <\/a> <\/h2>\n
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\n <\/td>\n <\/td>\n <\/td>\n <\/td>\n <\/td>\n <\/td>\n<\/tr>\n \n <\/td>\n <\/td>\n <\/td>\n <\/td>\n <\/td>\n <\/td>\n<\/tr>\n \n <\/td>\n <\/td>\n <\/td>\n <\/td>\n <\/td>\n \n <\/p>\nCONFORMING TO <\/a> <\/h2>\n
SEE ALSO <\/a> <\/h2>\n