NAME
wantread, fwantread - open file for reading
SYNOPSIS
#include <stdio.h>
#include <sys/file.h>
int wantread
(searchlist,filename,fullname,prompt);
const char *searchlist,*filename,*fullname,*prompt;
FILE *fwantread
(searchlist,filename,fullname,prompt);
const char *searchlist,*filename,*fullname,*prompt;
DESCRIPTION
Wantread attempts to open a file for input, asking the user
for an
alternate filename over and over again until a file is
successfully
opened for reading.
Searchlist is a list of
directories which may contain the file,
with the directory names separated by colons. Filename is
the name
of the file the program wishes to open; if filename is the
null
string, then the user will be asked immediately for the name
of a
file to open. When a file is opened, the complete filename
is
copied into fullname, which must be a string provided by the
user.
If openp(3) fails to open the
desired file, then an error message
is printed along with the message prompt, and the user can
type in
an alternate filename. The new file name is searched for
using the
same searchlist. The user may also indicate that no file is
acceptable; in this case, wantread will return an error
indication.
Fwantread is the same as
wantread, but uses fopenp(3) to open a
buffered file, and returns a FILE pointer.
SEE ALSO
openp(3), fopenp(3), wantwrite(3), fwantwrite(3)
DIAGNOSTICS
Wantread returns -1 on error; otherwise, the file descriptor
of the
successfully opened file.
Fwantread returns 0 on error, or
the FILE pointer of the
successfully fopened file.
BUGS
Fullname must be long enough to hold the complete filename
of the
opened file.
There should be a way to change
the value of searchlist if the
search for a file is unsuccessful.