Add empty-file check for memmep use in stdout

resolves #76

3 files changed, 62 insertions, 124 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 2d5e035..536a8f9 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -18,16 +18,15 @@ dependencies = [
 
 [[package]]
 name = "anyhow"
-version = "1.0.27"
+version = "1.0.28"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "assert_cmd"
-version = "1.0.0"
+version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "doc-comment 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "escargot 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "predicates 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "predicates-core 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "predicates-tree 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -39,8 +38,8 @@ name = "atty"
 version = "0.2.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "hermit-abi 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.68 (registry+https://github.com/rust-lang/crates.io-index)",
+ "hermit-abi 0.1.11 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.69 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -132,23 +131,12 @@ version = "1.5.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
-name = "escargot"
-version = "0.5.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde 1.0.105 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde_json 1.0.50 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
 name = "getrandom"
 version = "0.1.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "cfg-if 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.68 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.69 (registry+https://github.com/rust-lang/crates.io-index)",
  "wasi 0.9.0+wasi-snapshot-preview1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -162,34 +150,21 @@ dependencies = [
 
 [[package]]
 name = "hermit-abi"
-version = "0.1.8"
+version = "0.1.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "libc 0.2.68 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.69 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
-name = "itoa"
-version = "0.4.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
-[[package]]
 name = "lazy_static"
 version = "1.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "libc"
-version = "0.2.68"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
-[[package]]
-name = "log"
-version = "0.4.8"
+version = "0.2.69"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "cfg-if 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)",
-]
 
 [[package]]
 name = "man"
@@ -214,7 +189,7 @@ name = "memmap"
 version = "0.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "libc 0.2.68 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.69 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -228,11 +203,11 @@ dependencies = [
 
 [[package]]
 name = "num_cpus"
-version = "1.12.0"
+version = "1.13.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "hermit-abi 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.68 (registry+https://github.com/rust-lang/crates.io-index)",
+ "hermit-abi 0.1.11 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.69 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -265,11 +240,11 @@ dependencies = [
 
 [[package]]
 name = "proc-macro-error"
-version = "0.4.12"
+version = "1.0.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "proc-macro-error-attr 0.4.12 (registry+https://github.com/rust-lang/crates.io-index)",
- "proc-macro2 1.0.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro-error-attr 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro2 1.0.10 (registry+https://github.com/rust-lang/crates.io-index)",
  "quote 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "syn 1.0.17 (registry+https://github.com/rust-lang/crates.io-index)",
  "version_check 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -277,10 +252,10 @@ dependencies = [
 
 [[package]]
 name = "proc-macro-error-attr"
-version = "0.4.12"
+version = "1.0.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "proc-macro2 1.0.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro2 1.0.10 (registry+https://github.com/rust-lang/crates.io-index)",
  "quote 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "syn 1.0.17 (registry+https://github.com/rust-lang/crates.io-index)",
  "syn-mid 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -289,7 +264,7 @@ dependencies = [
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.9"
+version = "1.0.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "unicode-xid 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -300,7 +275,7 @@ name = "quote"
 version = "1.0.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "proc-macro2 1.0.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro2 1.0.10 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -309,7 +284,7 @@ version = "0.7.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "getrandom 0.1.14 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.68 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.69 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand_chacha 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand_core 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand_hc 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -359,7 +334,7 @@ dependencies = [
  "crossbeam-queue 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "crossbeam-utils 0.7.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "num_cpus 1.12.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "num_cpus 1.13.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -369,7 +344,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "regex"
-version = "1.3.6"
+version = "1.3.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "aho-corasick 0.7.10 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -397,11 +372,6 @@ version = "0.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
-name = "ryu"
-version = "1.0.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
-[[package]]
 name = "scopeguard"
 version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -410,69 +380,41 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 name = "sd"
 version = "0.7.4"
 dependencies = [
- "anyhow 1.0.27 (registry+https://github.com/rust-lang/crates.io-index)",
- "assert_cmd 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "anyhow 1.0.28 (registry+https://github.com/rust-lang/crates.io-index)",
+ "assert_cmd 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "man 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "memmap 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "rayon 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "regex 1.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
- "structopt 0.3.12 (registry+https://github.com/rust-lang/crates.io-index)",
+ "regex 1.3.7 (registry+https://github.com/rust-lang/crates.io-index)",
+ "structopt 0.3.14 (registry+https://github.com/rust-lang/crates.io-index)",
  "tempfile 3.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "thiserror 1.0.14 (registry+https://github.com/rust-lang/crates.io-index)",
+ "thiserror 1.0.15 (registry+https://github.com/rust-lang/crates.io-index)",
  "unescape 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
-name = "serde"
-version = "1.0.105"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "serde_derive 1.0.105 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "serde_derive"
-version = "1.0.105"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "proc-macro2 1.0.9 (registry+https://github.com/rust-lang/crates.io-index)",
- "quote 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "syn 1.0.17 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "serde_json"
-version = "1.0.50"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
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- "serde 1.0.105 (registry+https://github.com/rust-lang/crates.io-index)",
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-
-[[package]]
 name = "strsim"
 version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "structopt"
-version = "0.3.12"
+version = "0.3.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "clap 2.33.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "structopt-derive 0.4.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "structopt-derive 0.4.7 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "structopt-derive"
-version = "0.4.5"
+version = "0.4.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "heck 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "proc-macro-error 0.4.12 (registry+https://github.com/rust-lang/crates.io-index)",
- "proc-macro2 1.0.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro-error 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro2 1.0.10 (registry+https://github.com/rust-lang/crates.io-index)",
  "quote 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "syn 1.0.17 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -482,7 +424,7 @@ name = "syn"
 version = "1.0.17"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "proc-macro2 1.0.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro2 1.0.10 (registry+https://github.com/rust-lang/crates.io-index)",
  "quote 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "unicode-xid 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -492,7 +434,7 @@ name = "syn-mid"
 version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "proc-macro2 1.0.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro2 1.0.10 (registry+https://github.com/rust-lang/crates.io-index)",
  "quote 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "syn 1.0.17 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -503,7 +445,7 @@ version = "3.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "cfg-if 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.68 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.69 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand 0.7.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "redox_syscall 0.1.56 (registry+https://github.com/rust-lang/crates.io-index)",
  "remove_dir_all 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -520,18 +462,18 @@ dependencies = [
 
 [[package]]
 name = "thiserror"
-version = "1.0.14"
+version = "1.0.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "thiserror-impl 1.0.14 (registry+https://github.com/rust-lang/crates.io-index)",
+ "thiserror-impl 1.0.15 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "thiserror-impl"
-version = "1.0.14"
+version = "1.0.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "proc-macro2 1.0.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro2 1.0.10 (registry+https://github.com/rust-lang/crates.io-index)",
  "quote 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "syn 1.0.17 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -584,7 +526,7 @@ name = "wait-timeout"
 version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "libc 0.2.68 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.69 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -614,8 +556,8 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
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 "checksum ppv-lite86 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)" = "74490b50b9fbe561ac330df47c08f3f33073d2d00c150f719147d7c54522fa1b"
 "checksum predicates 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)" = "347a1b6f0b21e636bc9872fb60b83b8e185f6f5516298b8238699f7f9a531030"
 "checksum predicates-core 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "06075c3a3e92559ff8929e7a280684489ea27fe44805174c3ebd9328dcb37178"
 "checksum predicates-tree 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "8e63c4859013b38a76eca2414c64911fba30def9e3202ac461a2d22831220124"
-"checksum proc-macro-error 0.4.12 (registry+https://github.com/rust-lang/crates.io-index)" = "18f33027081eba0a6d8aba6d1b1c3a3be58cbb12106341c2d5759fcd9b5277e7"
-"checksum proc-macro-error-attr 0.4.12 (registry+https://github.com/rust-lang/crates.io-index)" = "8a5b4b77fdb63c1eca72173d68d24501c54ab1269409f6b672c85deb18af69de"
-"checksum proc-macro2 1.0.9 (registry+https://github.com/rust-lang/crates.io-index)" = "6c09721c6781493a2a492a96b5a5bf19b65917fe6728884e7c44dd0c60ca3435"
+"checksum proc-macro-error 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "98e9e4b82e0ef281812565ea4751049f1bdcdfccda7d3f459f2e138a40c08678"
+"checksum proc-macro-error-attr 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "4f5444ead4e9935abd7f27dc51f7e852a0569ac888096d5ec2499470794e2e53"
+"checksum proc-macro2 1.0.10 (registry+https://github.com/rust-lang/crates.io-index)" = "df246d292ff63439fea9bc8c0a270bed0e390d5ebd4db4ba15aba81111b5abe3"
 "checksum quote 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)" = "2bdc6c187c65bca4260c9011c9e3132efe4909da44726bad24cf7572ae338d7f"
 "checksum rand 0.7.3 (registry+https://github.com/rust-lang/crates.io-index)" = "6a6b1679d49b24bbfe0c803429aa1874472f50d9b363131f0e89fc356b544d03"
 "checksum rand_chacha 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "f4c8ed856279c9737206bf725bf36935d8666ead7aa69b52be55af369d193402"
@@ -657,24 +596,20 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum rayon 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "db6ce3297f9c85e16621bb8cca38a06779ffc31bb8184e1be4bed2be4678a098"
 "checksum rayon-core 1.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "08a89b46efaf957e52b18062fb2f4660f8b8a4dde1807ca002690868ef2c85a9"
 "checksum redox_syscall 0.1.56 (registry+https://github.com/rust-lang/crates.io-index)" = "2439c63f3f6139d1b57529d16bc3b8bb855230c8efcc5d3a896c8bea7c3b1e84"
-"checksum regex 1.3.6 (registry+https://github.com/rust-lang/crates.io-index)" = "7f6946991529684867e47d86474e3a6d0c0ab9b82d5821e314b1ede31fa3a4b3"
+"checksum regex 1.3.7 (registry+https://github.com/rust-lang/crates.io-index)" = "a6020f034922e3194c711b82a627453881bc4682166cabb07134a10c26ba7692"
 "checksum regex-syntax 0.6.17 (registry+https://github.com/rust-lang/crates.io-index)" = "7fe5bd57d1d7414c6b5ed48563a2c855d995ff777729dcd91c369ec7fea395ae"
 "checksum remove_dir_all 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)" = "4a83fa3702a688b9359eccba92d153ac33fd2e8462f9e0e3fdf155239ea7792e"
 "checksum roff 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "e33e4fb37ba46888052c763e4ec2acfedd8f00f62897b630cadb6298b833675e"
-"checksum ryu 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)" = "535622e6be132bccd223f4bb2b8ac8d53cda3c7a6394944d3b2b33fb974f9d76"
 "checksum scopeguard 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d29ab0c6d3fc0ee92fe66e2d99f700eab17a8d57d1c1d3b748380fb20baa78cd"
-"checksum serde 1.0.105 (registry+https://github.com/rust-lang/crates.io-index)" = "e707fbbf255b8fc8c3b99abb91e7257a622caeb20a9818cbadbeeede4e0932ff"
-"checksum serde_derive 1.0.105 (registry+https://github.com/rust-lang/crates.io-index)" = "ac5d00fc561ba2724df6758a17de23df5914f20e41cb00f94d5b7ae42fffaff8"
-"checksum serde_json 1.0.50 (registry+https://github.com/rust-lang/crates.io-index)" = "78a7a12c167809363ec3bd7329fc0a3369056996de43c4b37ef3cd54a6ce4867"
 "checksum strsim 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)" = "8ea5119cdb4c55b55d432abb513a0429384878c15dde60cc77b1c99de1a95a6a"
-"checksum structopt 0.3.12 (registry+https://github.com/rust-lang/crates.io-index)" = "c8faa2719539bbe9d77869bfb15d4ee769f99525e707931452c97b693b3f159d"
-"checksum structopt-derive 0.4.5 (registry+https://github.com/rust-lang/crates.io-index)" = "3f88b8e18c69496aad6f9ddf4630dd7d585bcaf765786cb415b9aec2fe5a0430"
+"checksum structopt 0.3.14 (registry+https://github.com/rust-lang/crates.io-index)" = "863246aaf5ddd0d6928dfeb1a9ca65f505599e4e1b399935ef7e75107516b4ef"
+"checksum structopt-derive 0.4.7 (registry+https://github.com/rust-lang/crates.io-index)" = "d239ca4b13aee7a2142e6795cbd69e457665ff8037aed33b3effdc430d2f927a"
 "checksum syn 1.0.17 (registry+https://github.com/rust-lang/crates.io-index)" = "0df0eb663f387145cab623dea85b09c2c5b4b0aef44e945d928e682fce71bb03"
 "checksum syn-mid 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)" = "7be3539f6c128a931cf19dcee741c1af532c7fd387baa739c03dd2e96479338a"
 "checksum tempfile 3.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "7a6e24d9338a0a5be79593e2fa15a648add6138caa803e2d5bc782c371732ca9"
 "checksum textwrap 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d326610f408c7a4eb6f51c37c330e496b08506c9457c9d34287ecc38809fb060"
-"checksum thiserror 1.0.14 (registry+https://github.com/rust-lang/crates.io-index)" = "f0570dc61221295909abdb95c739f2e74325e14293b2026b0a7e195091ec54ae"
-"checksum thiserror-impl 1.0.14 (registry+https://github.com/rust-lang/crates.io-index)" = "227362df41d566be41a28f64401e07a043157c21c14b9785a0d8e256f940a8fd"
+"checksum thiserror 1.0.15 (registry+https://github.com/rust-lang/crates.io-index)" = "54b3d3d2ff68104100ab257bb6bb0cb26c901abe4bd4ba15961f3bf867924012"
+"checksum thiserror-impl 1.0.15 (registry+https://github.com/rust-lang/crates.io-index)" = "ca972988113b7715266f91250ddb98070d033c62a011fa0fcc57434a649310dd"
 "checksum thread_local 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)" = "d40c6d1b69745a6ec6fb1ca717914848da4b44ae29d9b3080cbee91d72a69b14"
 "checksum treeline 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "a7f741b240f1a48843f9b8e0444fb55fb2a4ff67293b50a9179dfd5ea67f8d41"
 "checksum unescape 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ccb97dac3243214f8d8507998906ca3e2e0b900bf9bf4870477f125b82e68f6e"
diff --git a/Cargo.toml b/Cargo.toml
index 9fdc65b..0ca43b9 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -12,20 +12,20 @@ repository = "https://github.com/chmln/sd.git"
 categories = ["command-line-utilities", "text-processing", "development-tools"]
 
 [dependencies]
-regex = "1.3.6"
-structopt = "0.3.12"
+regex = "1.3.7"
+structopt = "0.3.14"
 rayon = "1.3.0"
 unescape = "0.1.0"
 memmap = "0.7.0"
 tempfile = "3.1.0"
-thiserror = "1.0.13"
+thiserror = "1.0.15"
 
 [dev-dependencies]
-assert_cmd = "1.0.0"
-anyhow = "1.0.27"
+assert_cmd = "1.0.1"
+anyhow = "1.0.28"
 
 [build-dependencies]
-structopt = "0.3.12"
+structopt = "0.3.14"
 man = "0.3.0"
 
 [profile.release]
diff --git a/src/input.rs b/src/input.rs
index 235ae68..b9982ed 100644
--- a/src/input.rs
+++ b/src/input.rs
@@ -171,6 +171,9 @@ impl Replacer {
                 let mut handle = stdout.lock();
 
                 paths.iter().try_for_each(|path| {
+                    if let Err(_) = Self::check_not_empty(File::open(path)?) {
+                        return Ok(());
+                    }
                     let file =
                         unsafe { memmap::Mmap::map(&File::open(path)?)? };
                     handle.write_all(&self.replace(&file))?;