GENWiki

Premier IT Outsourcing and Support Services within the UK

User Tools

Site Tools


man:vwarn

ERR(3) Linux Programmer's Manual ERR(3)

NAME

     err,  verr,  errx,  verrx, warn, vwarn, warnx, vwarnx - formatted error
     messages

SYNOPSIS

     #include <err.h>
     void err(int eval, const char *fmt, ...);
     void errx(int eval, const char *fmt, ...);
     void warn(const char *fmt, ...);
     void warnx(const char *fmt, ...);
     #include <stdarg.h>
     void verr(int eval, const char *fmt, va_list args);
     void verrx(int eval, const char *fmt, va_list args);
     void vwarn(const char *fmt, va_list args);
     void vwarnx(const char *fmt, va_list args);

DESCRIPTION

     The err() and warn() family of functions display a formatted error mes-
     sage on the standard error output.  In all cases, the last component of
     the program name, a colon character, and a space are  output.   If  the
     fmt argument is not NULL, the printf(3)-like formatted error message is
     output.  The output is terminated by a newline character.
     The err(), verr(), warn(), and vwarn() functions append an  error  mes-
     sage obtained from strerror(3) based on the global variable errno, pre-
     ceded by another colon and space unless the fmt argument is NULL.
     The errx() and warnx() functions do not append an error message.
     The err(), verr(), errx(), and verrx() functions  do  not  return,  but
     exit with the value of the argument eval.

ATTRIBUTES

     For   an   explanation   of   the  terms  used  in  this  section,  see
     attributes(7).
     allbox; lbw17 lb lb l l l.  Interface Attribute Value T{ err(), errx(),
     warn(), warnx(),
     verr(), verrx(),
     vwarn(), vwarnx() T}   Thread safety  MT-Safe locale

CONFORMING TO

     These functions are nonstandard BSD extensions.

EXAMPLE

     Display the current errno information string and exit:
         p = malloc(size); if (p == NULL)
             err(1, NULL); fd = open(file_name, O_RDONLY, 0); if (fd == -1)
             err(1, "%s", file_name);
     Display an error message and exit:
         if (tm.tm_hour < START_TIME)
             errx(1, "too early, wait until %s", start_time_string);
     Warn of an error:
         fd = open(raw_device, O_RDONLY, 0); if (fd == -1)
             warnx("%s: %s: trying the block device",
                     raw_device,  strerror(errno));  fd = open(block_device,
         O_RDONLY, 0); if (fd == -1)
             err(1, "%s", block_device);

SEE ALSO

     error(3), exit(3), perror(3), printf(3), strerror(3)

COLOPHON

     This page is part of release 4.16 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/.

Linux 2017-09-15 ERR(3)

/data/webs/external/dokuwiki/data/pages/man/vwarn.txt · Last modified: 2019/05/17 09:47 by 127.0.0.1

Was this page helpful?-11+1

Donate Powered by PHP Valid HTML5 Valid CSS Driven by DokuWiki