[llvm] [llvm-lit][test] Precommit tests for lit's built-in cat command (PR #101530)

[via llvm-commits]

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@@ -0,0 +1,49 @@
+# C Program to generate all ASCII characters in allchars.txt
+# #include <stdio.h>
+# int main() {
+#     FILE *fptr = fopen("allchars.txt", "w");
+#     if(fptr == NULL) {
+#         return 1;
+#     }
+#     for(int i = 0; i < 256; i++) {
+#         fprintf(fptr, "%c", i);
+#     }
+#     fclose(fptr);
+#     return 0;
+# }
+
+
+## Tests to check cat -e output for ASCII characters and newlines
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connieyzhu wrote:

done

https://github.com/llvm/llvm-project/pull/101530