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| author | Mole Shang <135e2@135e2.dev> | 2024-02-16 10:20:27 +0800 |
|---|---|---|
| committer | Mole Shang <135e2@135e2.dev> | 2024-02-16 10:20:27 +0800 |
| commit | a98c56a811142e5ede3332a7a444cca45f628769 (patch) | |
| tree | c93ff7090da7b6ef911932be283818c2f6a03784 /user/pingpong.c | |
| parent | 0d65be5d1d880afafbf08c2adb605cf9f72216e2 (diff) | |
| parent | 99015f3a985b2fd051606636743a2a2969b216e8 (diff) | |
| download | xv6-labs-a98c56a811142e5ede3332a7a444cca45f628769.tar.gz xv6-labs-a98c56a811142e5ede3332a7a444cca45f628769.tar.bz2 xv6-labs-a98c56a811142e5ede3332a7a444cca45f628769.zip | |
Merge branch 'lock' into thread
Conflicts:
.gitignore
Makefile
conf/lab.mk
Diffstat (limited to 'user/pingpong.c')
| -rw-r--r-- | user/pingpong.c | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/user/pingpong.c b/user/pingpong.c new file mode 100644 index 0000000..7b03a76 --- /dev/null +++ b/user/pingpong.c @@ -0,0 +1,44 @@ +#include "kernel/types.h" +#include "user/user.h" + +int +main(int argc, char* argv[]) +{ + int p[2]; + + if (argc > 1) { + fprintf(2, "usage: pingpong\n"); + exit(1); + } + + pipe(p); + + int pid = fork(); + + if (pid == 0) { + short n; + read(p[0], &n, sizeof(n)); + if (n == 42) { + fprintf(1, "%d: received ping\n", getpid()); + } + n++; + write(p[1], &n, sizeof(n)); + close(p[0]); + close(p[1]); + exit(0); + } + + short n = 42; + + write(p[1], &n, sizeof(n)); + read(p[0], &n, sizeof(n)); + if (n == 43) { + fprintf(1, "%d: received pong\n", getpid()); + } + close(p[0]); + close(p[1]); + + wait(0); + + exit(0); +} |