isfdtype(3)                Library Functions Manual                isfdtype(3)

NAME
       isfdtype - test file type of a file descriptor

LIBRARY
       Standard C library (libc, -lc)

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 failure, -1 is returned and errno is set
       to indicate the error.

ERRORS
       The isfdtype() function can fail with any of the same errors as
       fstat(2).

VERSIONS
       Portable applications should use fstat(2) instead.

STANDARDS
       None.

HISTORY
       It appeared 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).

SEE ALSO
       fstat(2)

Linux man-pages 6.7               2023-10-31                       isfdtype(3)