NAME

       isfdtype - test file type of a file descriptor

SYNOPSIS

       #include <sys/stat.h>
       #include <sys/socket.h>

       int isfdtype(int fd, int fdtype);

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

       isfdtype():
           Since glibc 2.20:
               _DEFAULT_SOURCE
           Before glibc 2.20:
               _BSD_SOURCE || _SVID_SOURCE

DESCRIPTION

       The  isfdtype()  function  tests  whether  the file descriptor fd refers to a file of type
       fdtype.  The fdtype argument specifies one of the S_IF* constants defined in  <sys/stat.h>
       and documented in stat(2) (e.g., S_IFREG).

RETURN VALUE

       The  isfdtype() function returns 1 if the file descriptor fd is of type fdtype and 0 if it
       is not.  On error, -1 is returned and errno is set to indicate the cause.

ERRORS

       The isfdtype() function can fail with any of the same errors as fstat(3).

CONFORMING TO

       The isfdtype() function is not specified in any standard, but  did  appear  in  the  draft
       POSIX.1g  standard.   It  is  present on OpenBSD and Tru64 UNIX (where the required header
       file in both cases is just <sys/stat.h>, as shown in the  POSIX.1g  draft),  and  possibly
       other systems.

NOTES

       Portable applications should use fstat(3) instead.

SEE ALSO

       fstat(3)

COLOPHON

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