isastream(3C)

isastream -- test a file descriptor

Synopsis

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

Description

The function isastream determines if a file descriptor represents a STREAMS file. fildes refers to an open file.

Return values

On success, isastream returns 1 if fildes represents a STREAMS file, and 0 if not. On failure, isastream returns -1 and sets errno to identify the error.

Errors

Under the following conditions, isastream fails and sets errno to:

EBADF: fildes is not a valid open file.

References

streamio(7), unistd(4)