isatty(3) - Linux man page
Name
isatty - test whether a file descriptor refers to a terminal
Synopsis
#include <unistd.h>
int isatty(int fd);
Description
The isatty() function tests whether fd is an open file descriptor referring to a terminal.
Return Value
isatty() returns 1 if fd is an open file descriptor referring to a terminal; otherwise 0 is
returned, and errno is set to indicate the error.
Errors
- EBADF
- fd is not a valid file descriptor.
- EINVAL
- fd refers to a file other than a terminal. POSIX.1-2001 specifies the error ENOTTY for this case.
Conforming to
SVr4, 4.3BSD, POSIX.1-2001.
See Also
fstat(2), ttyname(3)
Referenced By
mailcap(4),
sh(1),
tcpslice(8)