NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | ATTRIBUTES | SEE ALSO
#include <arpa/telnetd.h>int telnetdReadLine(telnetdSessionHandle *hdl, void *buf, unsigned int nchar, int echo, char *prompt);
The telnetdReadLine function attempts to read a line of characters from the TELNET session designated by the hdl handle into the buffer pointed to by buf. A line is delimited by a NEWLINE (ASCII LF) character. This means that telnetdReadLine will not complete until an entire line has been typed. However, nchar indicates the maximum number of characters to be read. Any number of characters may be requested in telnetdReadLine, even one, without losing information. Also, no matter how many characters are requested by the call, a maximum of one line will be returned.
If the value of echo is not zero, characters read from the TELNET session will be echoed on the user terminal. Otherwise, no echoing will be performed.
If prompt is not the NULL pointer, telnetdReadLine first writes the string (terminated by a null character) pointed to by prompt on the TELNET connection.
If the TELNET session has no data available and the connection socket has O_NONBLOCK set, telnetdReadLine returns -1 and sets errno to EAGAIN. Otherwise, telnetdReadLine blocks until a line of characters becomes available.
As described in telnetdRead, the application should check if on return of telnetdReadLine the state of the virtual terminal has changed, and get the new state by calling telnetdGetTermState.
Upon successful completion, telnetdReadLine returns the number of characters actually read and placed in the buffer; this number may be less than nchar. Otherwise it returns -1 and sets errno to indicate the error.
errno is set to EINVAL if telnetdReadLine is called with an invalid hdl handle.
The telnetdReadLine function may fail and set errno to any of the errors specified for the telnetdRead(3TELD) and telnetdWrite(3TELD) functions.
See attributes(5) for descriptions of the following attributes:
ATTRIBUTE TYPE | ATTRIBUTE VALUE |
---|---|
Interface Stability | Evolving |
NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | ATTRIBUTES | SEE ALSO