To urinate beside one's companion while screened by a wall Sahih al-Bukhari 225
Arabic hadith text
حَدَّثَنَا عُثْمَانُ بْنُ أَبِي شَيْبَةَ، قَالَ حَدَّثَنَا جَرِيرٌ، عَنْ مَنْصُورٍ، عَنْ أَبِي وَائِلٍ، عَنْ حُذَيْفَةَ، قَالَرَأَيْتُنِي أَنَا وَالنَّبِيُّ، صلى الله عليه وسلم نَتَمَاشَى، فَأَتَى سُبَاطَةَ قَوْمٍ خَلْفَ حَائِطٍ، فَقَامَ كَمَا يَقُومُ أَحَدُكُمْ فَبَالَ، فَانْتَبَذْتُ مِنْهُ، فَأَشَارَ إِلَىَّ فَجِئْتُهُ، فَقُمْتُ عِنْدَ عَقِبِهِ حَتَّى فَرَغَ.
Translation
Narrated Hudhaifa'
The Prophet (ﷺ) and I walked till we reached the dumps of some people. He stood, as any one of you stands, behind a wall and urinated. I went away, but he beckoned me to come. So I approached him and stood near his back till he finished.