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In case a system call function fails, we normally use perror to output the error message. I want to use fprintf to output the perror string. How can I do something like this: 

fprintf(stderr, perror output string here);
Mateusz Piotrowski
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RajSanpui
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1 Answers1

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#include <errno.h>

fprintf(stderr, "%s\n", strerror(errno));

Note: strerror doesn't apply \n to the end of the message

maverik
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  • Thanks maverik. But the output will be exactly identical to perror string? – RajSanpui Mar 30 '11 at 07:24
  • So i am doing something like this: `fprintf(stderr, "LeakTracer: timer_settime failed to set timer (timer_trackStartTime): %s \n",strerror(errno);` – RajSanpui Mar 30 '11 at 07:30
  • Not exactly the same. When using perror usually you write: `perror("fopen")`. This results in `"fopen: "`. In case of `fprintf(stderr, "%s\n", strerror(errno))` you should give: ``, so if you need exactly the same, use: `fprintf(stderr, "fopen: %s\n", strerror(errno))`. Of course you should replace `fopen` by the name of your function – maverik Mar 30 '11 at 07:30