Sometimes, LD_PRELOAD in HPUX and Solaris cannot take effect

Question

I get some problem about LD_PRELOAD.

When I use LD_PRELOAD in HPUX and Solaris, I found that I cannot attach my open64/open/creat64/creat function in /usr/bin/touch, but my unlink can take effect in /usr/bin/rm, why?

I have do a simple test:

int open(int fd, int flag, mode_t mode) 
{
    return -1;
}

int open64(int fd, int flag, mode_t mode) 
{
    return -1;
}

int creat(int fd, mode_t mode)
{
    return -1;
}

int creat64(int fd, mode_t mode)
{
    return -1;
}

when i do this, i found : normally, i cannot open file, but touch can do it!

why!i was puzzled by this for long time. who can help me.thx

at last, sorry for my poor English

yes. the command `truss -o touch.log touch testfile` told me that, it uses creat64 function to creat file. — littletiny, Dec 28 '11 at 01:55
Make sure you are executing `/usr/bin/touch` and not your shell's built-in `touch` command. — Piotr Praszmo, Dec 31 '11 at 11:37

Chris · Answer 1 · 2011-12-31T11:23:20.123

1

i think your function signature is wrong. (int instead of char *) on my system i see the following signature:

grep -w creat /usr/include/*

/usr/include/fcntl.h:#define    creat64     creat
/usr/include/fcntl.h:extern int creat(const char *, mode_t);

grep -w open /usr/include/*

/usr/include/fcntl.h:#define    open64      open
/usr/include/fcntl.h:extern int open(const char *, int, ...);

edited Dec 31 '11 at 11:23

answered Dec 31 '11 at 11:17

Chris

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Sometimes, LD_PRELOAD in HPUX and Solaris cannot take effect

1 Answers1