thanks monk, for example, if i write a C program as below: main() { exit(100); } then, i invoke it from perl, and print the exit code, it's 25600. it convert to binary is: 1100100 00000000. so the high 8 bits is: 1100100(100), and the low 8 bits is: 00000000. if this C programm ran abnormally, the low 8 bits may contain info of interest, so use $? & 127 OR $? & 128. am'i right?

In reply to Re^2: why divide 256 for the exit code by zhujian0805
in thread why divide 256 for the exit code by zhujian0805

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