plan9port/man/man3/readcons.3
Russ Cox 977b25a76a tmac: introduce real manual reference macro instead of overloading IR
The overloading of IR emits magic \X'...' sequences that turn into HTML manual links.
But not all such IR invocations should be manual links;
those had to be written to avoid the IR macro before.
Worse, the \X'...' ending the IR causes troff to emit only a single space after a period.

Defining a new IM macro for manual references fixes both problems.

Fixes #441.
2020-08-13 23:43:43 -04:00

50 lines
990 B
Groff

.TH READCONS 3
.SH NAME
readcons \- prompt console for input
.SH SYNOPSIS
.B
#include <u.h>
.PP
.B
#include <libc.h>
.PP
.B
char *readcons(char *prompt, char *def, int secret)
.SH DESCRIPTION
.I Readcons
prompts at the console for input.
It returns a NUL-terminated buffer containing the input
without a final newline.
The buffer should be freed (and perhaps cleared first)
when no longer needed.
.PP
If the user types an empty string (just a newline) and
.I def
is non-zero, then a copy of
.I def
is returned instead of the empty string.
.PP
If
.I secret
is non-zero, the input is not echoed to the screen.
.SH EXAMPLE
A stripped-down version of
.I netkey
(see
.IM passwd (1) ):
.IP
.EX
pass = readcons("password", nil, 1);
passtokey(key, pass);
memset(pass, 0, strlen(pass));
free(pass);
for(;;){
chal = readcons("challenge", nil, 0);
sprint(buf, "%d", strtol(chal, 0, 10));
free(chal);
netcrypt(key, buf);
print("response: %s\n", buf);
}
.EE
.SH SOURCE
.B \*9/src/lib9/readcons.c