NAME

isastream() − determine if a file descriptor refers to a STREAMS device or STREAMS-based pipe

SYNOPSIS

#include <stropts.h>
int isastream(int fd);

DESCRIPTION

The isastream() function tests whether an open file descriptor ( fd ) corresponds to a STREAMS device or STREAMS-based pipe. 

RETURN VALUE

Upon successful completion, the isastream() function returns a value of 1 when the file descriptor of the open file specified by fd is a STREAMS device or STREAMS-based pipe, and 0 (zero) if it is not a stream, but is a valid open file descriptor.  Otherwise, a value of -1 is returned, and errno is set to indicate the error. 

ERRORS

If any of the following conditions occur, the isastream() function sets errno to the corresponding value:

[EBADF] The specified file descriptor does not refer to a valid open file. 

SEE ALSO

fattach(3c), fdetach(3c), streamio(7). 

STANDARDS COMPLIANCE

isastream(): SVID3

Hewlett-Packard Company  —  HP-UX Release 10.20:  July 1996