45 lines
961 B
C
45 lines
961 B
C
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#include <sys/types.h>
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#include <sys/wait.h>
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#include <errno.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <sysexits.h>
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#include <unistd.h>
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char * get_input(char *buffer, size_t buflen) {
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printf("$$ ");
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return fgets(buffer, buflen, stdin);
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}
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int main(int argc, char **argv) {
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char buf[BUFSIZ];
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pid_t pid;
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int status;
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// Cast to void to prevent compiler warning
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(void)argc;
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(void)argv;
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while(get_input(buf, sizeof(buf))) {
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buf[strlen(buf) - 1] = '\0';
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if ((pid = fork()) == -1) {
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fprintf(stderr, "SHELL: Can’t fork: %s\n", strerror(errno));
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continue;
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} else if (pid == 0) {
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execlp(buf, buf, (char *)0);
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fprintf(stderr, "SHELL: Can’t exec %s: %s\n", buf, strerror(errno));
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exit(EX_UNAVAILABLE);
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}
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// Parent waits
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if ((pid = waitpid(pid, &status, 0)) < 0) {
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fprintf(stderr, "SHELL: waitpid error: %s\n", strerror(errno));
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}
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}
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exit(EX_OK);
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}
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