Failing to open() a file

[sa125]

Hi - I'm using the open() function to open an existing file on linux. I keep getting a failure return value (-1 in this case) when trying to do so:

int result = open("/tmp/my_file" , O_RDONLY);

The file exists and I have permissions on it. This is driving me crazy - I'd appreciate any help on this - thanks.

[QuantumPete]

I always thought C uses fopen() to open files.

QuantumPete

[C_ntua]

open() is used, also, in linux
Is this the first time it is open it in the program? Can you generally use the file from the OS? Like try editing it and see

[QuantumPete]

In that case "man open" yields the following:

Otherwise, -1 is returned, errno is set to indicate the error

it then goes on to list the errors that could occur with open(). On Linux, man should always be your first port of call for these things, in other words, RTFM.

QuantumPete

[mageshd84]

try using perror() to if 'result' is negative. it will give you more information on the error.