I need to get the size of a C/C++ executable at runtime in code. Unfortunately I cannot use /proc/self/exe as it's restricted on the target system.
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Isnt the exe path given in the first argument to main? Can you get size from there? – pacukluka May 13 '20 at 02:56
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https://stackoverflow.com/questions/1023306/finding-current-executables-path-without-proc-self-exe?rq=1 may help – Nate Eldredge May 13 '20 at 02:58
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1Does [`dl_iterate_phdr`](http://man7.org/linux/man-pages/man3/dl_iterate_phdr.3.html) help? – o11c May 13 '20 at 03:05
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From experimenting, casting `info->dlpi_addr` to `ElfW(Ehdr)*` and calculating the end of the section headers is usually the end of the file. Of course, it's not *guaranteed* that section headers will be the last meaningful thing in the file, and there could always be some trailing junk ... – o11c May 13 '20 at 04:32
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dl_iterate_phdr seems to do the trick! – jestro May 14 '20 at 21:24
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Actually, it's a lot simpler than my attempt in the comments. The executable is simply:
(const char *)getauxval(AT_EXECFN)
That said, you should always try to open /proc/self/exe first since the executable may have been deleted/moved/replaced while running.
o11c
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First string in argv should be path used to run the executable. You can use std::filesystem::file_size to get the size.
In an exceptional case, where the command is a plain basename without a path separator, you need to search for it from the directories in the $PATH env variable.
eerorika
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