[MAN] perror

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PERROR

Section: MySQL Database System (1)
Updated: 06/07/2022
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NAME

perror - display MySQL error message information  

SYNOPSIS

perror [options] errorcode ...

 

DESCRIPTION

For most system errors, MySQL displays, in addition to an internal text message, the system error code in one of the following styles:

message ... (errno: #)
message ... (Errcode: #)

You can find out what the error code means by examining the documentation for your system or by using the perror utility.

perror prints a description for a system error code or for a storage engine (table handler) error code.

Invoke perror like this:

perror [options] errorcode ...

Examples:

$> perror 1231
MySQL error code 1231 (ER_WRONG_VALUE_FOR_VAR): Variable '%-.64s' can't
be set to the value of '%-.200s'

$> perror 13 64
OS error code  13:  Permission denied
OS error code  64:  Machine is not on the network

To obtain the error message for a MySQL Cluster error code, use the ndb_perror utility.

The meaning of system error messages may be dependent on your operating system. A given error code may mean different things on different operating systems.

perror supports the following options.

• --help, --info, -I, -? Display a help message and exit.

• --ndb Print the error message for an NDB Cluster error code.

This option is deprecated in NDB 7.6.4 and later, where perror prints a warning if it is used, and is removed in NDB Cluster 8.0. Use the ndb_perror utility instead.

• --silent, -s Silent mode. Print only the error message.

• --verbose, -v Verbose mode. Print error code and message. This is the default behavior.

• --version, -V Display version information and exit.

 

COPYRIGHT

Copyright © 1997, 2022, Oracle and/or its affiliates.

This documentation is free software; you can redistribute it and/or modify it only under the terms of the GNU General Public License as published by the Free Software Foundation; version 2 of the License.

This documentation is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with the program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA or see http://www.gnu.org/licenses/.

 

SEE ALSO

For more information, please refer to the MySQL Reference Manual, which may already be installed locally and which is also available online at http://dev.mysql.com/doc/.  

AUTHOR

Oracle Corporation (http://dev.mysql.com/).

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Index

NAME

SYNOPSIS

DESCRIPTION

COPYRIGHT

SEE ALSO

AUTHOR

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PERROR

Section: Linux Programmer's Manual (3)
Updated: 2017-09-15
Index Return to Main Contents

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NAME

perror - print a system error message  

SYNOPSIS

#include <stdio.h>

void perror(const char *s);

#include <errno.h>

const char * const sys_errlist[];
int sys_nerr;
int errno; /* Not really declared this way; see errno(3) */

Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

sys_errlist, sys_nerr:
    Since glibc 2.19:
        _DEFAULT_SOURCE
    Glibc 2.19 and earlier:
        _BSD_SOURCE  

DESCRIPTION

The perror() function produces a message on standard error describing the last error encountered during a call to a system or library function.

First (if s is not NULL and *s is not a null byte ('\0')), the argument string s is printed, followed by a colon and a blank. Then an error message corresponding to the current value of errno and a new-line.

To be of most use, the argument string should include the name of the function that incurred the error.

The global error list sys_errlist[], which can be indexed by errno, can be used to obtain the error message without the newline. The largest message number provided in the table is sys_nerr-1. Be careful when directly accessing this list, because new error values may not have been added to sys_errlist[]. The use of sys_errlist[] is nowadays deprecated; use strerror(3) instead.

When a system call fails, it usually returns -1 and sets the variable errno to a value describing what went wrong. (These values can be found in <errno.h>.) Many library functions do likewise. The function perror() serves to translate this error code into human-readable form. Note that errno is undefined after a successful system call or library function call: this call may well change this variable, even though it succeeds, for example because it internally used some other library function that failed. Thus, if a failing call is not immediately followed by a call to perror(), the value of errno should be saved.  

ATTRIBUTES

For an explanation of the terms used in this section, see attributes(7).

Interface	Attribute	Value
perror()	Thread safety	MT-Safe race:stderr

 

CONFORMING TO

perror(), errno: POSIX.1-2001, POSIX.1-2008, C89, C99, 4.3BSD.

The externals sys_nerr and sys_errlist derive from BSD, but are not specified in POSIX.1.  

NOTES

The externals sys_nerr and sys_errlist are defined by glibc, but in <stdio.h>.  

SEE ALSO

err(3), errno(3), error(3), strerror(3)  

COLOPHON

This page is part of release 4.15 of the Linux man-pages project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.

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Index

NAME

SYNOPSIS

DESCRIPTION

ATTRIBUTES

CONFORMING TO

NOTES

SEE ALSO

COLOPHON

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This document was created by man2html, using the manual pages.
Time: 04:45:43 GMT, September 16, 2022