We can use the system function to run an external command. The method invokes the command synchronously and return the status code. Given the following C program, we first concatenate all command line paramters into a string/char buffer of size 256. And then we invoke the command string using system function from stdlib header. And return the status code as the main function.
This is just a wrapper of the command. You can echo $? to see the status code:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 | #include <stdlib.h> #include <stdio.h> #include <string.h> int main(int argc, char* argv[]) { if (argc == 0) { return 0; } char cmd[255]; int s = 0; for (int i = 1; i < argc; ++ i) { strcpy(cmd + s, argv[i]); s += strlen(argv[i]); cmd[s ++] = ' '; } cmd[s] = '\0'; printf("Running `%s` ...\n", cmd); int ret = system(cmd); printf("Return Code: %d\n", ret); return ret; } |
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
int main(int argc, char* argv[]) {
if (argc == 0) {
return 0;
}
char cmd[255];
int s = 0;
for (int i = 1; i < argc; ++ i) {
strcpy(cmd + s, argv[i]);
s += strlen(argv[i]);
cmd[s ++] = ' ';
}
cmd[s] = '\0';
printf("Running `%s` ...\n", cmd);
int ret = system(cmd);
printf("Return Code: %d\n", ret);
return ret;
}Compiling the above C source e.g. run.c
1 | $ gcc run.c -o run |
$ gcc run.c -o run
And then run:
1 2 3 4 5 6 | $ ./run echo HelloACM.com Running `echo HelloACM.com ` ... HelloACM.com Return Code: 0 $ echo $? 0 |
$ ./run echo HelloACM.com Running `echo HelloACM.com ` ... HelloACM.com Return Code: 0 $ echo $? 0
–EOF (The Ultimate Computing & Technology Blog) —
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