struct stat st; stat(fileName.c_str(), &st); hu?

[Steven T. Hatton]

I found the following two statements in the file linked below:

struct stat st;
stat(fileName.c_str(), &st);

http://websvn.kde.org/branches/work/kdevelop4-parser/main.cpp?rev=420247&view=markup

This is from /usr/include/sys/stat.h which I'm pretty sure is what #include
<sys/stat.h> is pulling in. I plain and simply do not understand what the
above two lines of code do. Can someone please explain?

extern int stat (__const char *__restrict __file,
struct stat *__restrict __buf) __THROW;

 

[Pete Becker]

I found the following two statements in the file linked below:

struct stat st;
stat(fileName.c_str(), &st);

http://websvn.kde.org/branches/work/kdevelop4-parser/main.cpp?rev=420247&view=markup

This is from /usr/include/sys/stat.h which I'm pretty sure is what #include
<sys/stat.h> is pulling in. I plain and simply do not understand what the
above two lines of code do. Can someone please explain?

extern int stat (__const char *__restrict __file,
struct stat *__restrict __buf) __THROW;

Pretend it says this:

struct stat
{
// whatever...
};

extern int STAT(const char *, struct stat *);

struct stat st; // defines object of type struct stat
STAT(fileName.c_str(), &st); // call STAT

This is a quirk in the standard C library: there's a struct named 'stat'
and a function named 'stat'. When you say "struct stat" you're talking
about the struct; when you say "stat" you're talking about the function.

 

[Jack Klein]

Pretend it says this:

struct stat
{
// whatever...
};

extern int STAT(const char *, struct stat *);

struct stat st; // defines object of type struct stat
STAT(fileName.c_str(), &st); // call STAT

This is a quirk in the standard C library: there's a struct named 'stat'
and a function named 'stat'. When you say "struct stat" you're talking
about the struct; when you say "stat" you're talking about the function.

If it was anyone who didn't work for Dinkumware, I'd have to point
that the problem is not with the "standard C" library.

Oh, what the heck, I just did that anyway.

 

[Pete Becker]

If it was anyone who didn't work for Dinkumware, I'd have to point
that the problem is not with the "standard C" library.

Oh, what the heck, I just did that anyway.

Good point. It's not the standard C library; it's the usual C library,
i.e., a UNIXism incorporated into POSIX and into most C libraries. I
don't know of any other code that does this, and it required a change to
the original grammar in C++ to make it work.