receiving stderr and stdout from popen

This is a discussion on receiving stderr and stdout from popen within the C Programming forums, part of the General Programming Boards category; Hello all, consider the code for running an external process and receiving the output: Code: read_fp = popen(system_call,"r"); if (read_fp ...

  1. #1
    Registered User
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    Aug 2002
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    351

    receiving stderr and stdout from popen

    Hello all,

    consider the code for running an external process and receiving the output:
    Code:
            read_fp = popen(system_call,"r");
            if (read_fp != NULL)
            {
                    chars_read = fread(sys_result, sizeof(char), sizeof(my_var)-1,                      read_fp);	
                    pclose(read_fp);
            }
    i want to be able to receive the stdout stream and not the stderr stream.

    is this done by popen by default, or will i have to change the system_call or the external process?

    i think i've just answered my question!!! maybe cat "2>/dev/null" on the end of system_call???

    i would still like to know about popen though.

    TIA, rotis23

  2. #2
    End Of Line Hammer's Avatar
    Join Date
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    Posts
    6,231
    You can also use pipe() and fork(), which is what I *believe* popen() does anyway. There's sample code of this somewhere, I thought it was here but it doesn't look like I remember Anyway, it may help you.
    When all else fails, read the instructions.
    If you're posting code, use code tags: [code] /* insert code here */ [/code]

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