On Nov 20, 2:45 pm, Johannes Bauer <dfnsonfsdu...@gmx.dewrote:
coming from C, I'm used to somthing like this when opening a file
const char *foobar = "this.txt";
FILE *f;
f = fopen(foobar, "r");
if (!f) {
fprintf(stderr, "Couldn't open %s: %s\n", foobar, strerror(errno));
exit(EXIT_FAILURE);
}
translating that somewhat to C++ yields me with
const char *foobar = "this.txt";
std::ifstream f(foobar);
if (!f) {
throw GenericException("Couldn't open file.");
}
So I can detect that opening the file wasn't successful, but I
don't know *why* (i.e. permissions, no such file or directory,
etc.). My guess is that strerror and errno still do what I
expect them to do, however I think that would be a very C-way
to solve things.
It's not really a C way either, since C doesn't say anything
about the state of errno after a failed fopen.
Pragmatically, it's what I do as well.
How can I accomplish strerror(errno) on the std::ifstream with
C++ means?
You can't associate errno with an std::ifstream anymore than you
can associate it a FILE*.
--
James Kanze (GABI Software) email:james.kanze@gmail.com
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