pwd: /out/package
ppid: 246
   1: WRITELN echo 123 > 1.txt
   2: WRITELN echo 321 > 2.txt
   3: WRITELN echo abc < 1.txt < 2.txt
   4: WRITELN echo abc | grep abc < 1.txt
   5: WRITELN exit

mumsh $ mumsh $ mumsh $ error: duplicated input redirection
mumsh $ error: duplicated input redirection
mumsh $ exit

=================================================================
==247==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 13312 byte(s) in 13 object(s) allocated from:
    #0 0x4dd210  (/out/package/mumsh_memory_check+0x4dd210)
    #1 0x5165f8  (/out/package/mumsh_memory_check+0x5165f8)
    #2 0x7ff70cb7eb96  (/lib/x86_64-linux-gnu/libc.so.6+0x21b96)

SUMMARY: AddressSanitizer: 13312 byte(s) leaked in 13 allocation(s).

mumsh $ mumsh $ mumsh $ error: duplicated input redirection
mumsh $ error: duplicated input redirection
mumsh $ exit