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+% CALCTDIFF(1) calctdiff VERSION | User Commands Manual
+changequote(`{{{', `}}}')%
+% syscmd({{{date --date=@"$({ git log -1 --pretty="format:%ct%n" '}}}THIS{{{'; date +"%s"; } | head -n 1)" +"%Y-%m-%d %H:%M:%S"}}})
+undefine({{{VERSION}}})
+undefine({{{THIS}}})
+
+# NAME
+
+**calctdiff** — calculate time differences
+
+# SYNOPSIS
+
+| **calctdiff** BEGIN_DATE END_DATE
+
+# DESCRIPTION
+
+Calculate the time difference between two dates. The output result is
+`(END_DATE - BEGIN_DATE)`. The provided dates may use any syntax parseable by
+`date(1)`. If END_DATE is not given, current date is used.
+
+# OPTIONS
+
+No options accepted.
+
+# EXAMPLES
+
+```
+$ calctdiff 2020-10-11 2024-09-06
+1426 days, 0 hours, 0 minutes, 0 seconds
+
+$ calctdiff 2020-10-11
+1426 days, 0 hours, 0 minutes, 0 seconds
+
+$ calctdiff 2020-10-11 "@$(date +%s)"
+1426 days, 1 hours, 22 minutes, 1 seconds
+```
+
+# AUTHOR
+
+Berke Kocaoğlu <berke.kocaoglu@icloud.com>
+
+# BUGS & ISSUES
+
+Report at <https://github.com/XPhyro/scripts/issues> or
+<https://codeberg.org/XPhyro/scripts/issues>, or mail the author.
+GitHub is preferred.
+
+# COPYRIGHT
+
+include({{{LICENSE}}})
+
+# SEE ALSO
+
+date(1)